diff --git a/impit-python/python/impit/impit.pyi b/impit-python/python/impit/impit.pyi
index f1667a53..2dd2abd4 100644
--- a/impit-python/python/impit/impit.pyi
+++ b/impit-python/python/impit/impit.pyi
@@ -518,7 +518,7 @@ class Client:
     def get(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -538,7 +538,7 @@ class Client:
     def post(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -559,7 +559,7 @@ class Client:
     def put(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -579,7 +579,7 @@ class Client:
     def patch(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -599,7 +599,7 @@ class Client:
     def delete(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -619,7 +619,7 @@ class Client:
     def head(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -639,7 +639,7 @@ class Client:
     def options(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -659,7 +659,7 @@ class Client:
     def trace(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -680,7 +680,7 @@ class Client:
         self,
         method: str,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -704,7 +704,7 @@ class Client:
         self,
         method: str,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -859,7 +859,7 @@ class AsyncClient:
     async def get(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -879,7 +879,7 @@ class AsyncClient:
     async def post(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -900,7 +900,7 @@ class AsyncClient:
     async def put(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -920,7 +920,7 @@ class AsyncClient:
     async def patch(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -940,7 +940,7 @@ class AsyncClient:
     async def delete(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -960,7 +960,7 @@ class AsyncClient:
     async def head(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -980,7 +980,7 @@ class AsyncClient:
     async def options(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1000,7 +1000,7 @@ class AsyncClient:
     async def trace(
         self,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1021,7 +1021,7 @@ class AsyncClient:
         self,
         method: str,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1045,7 +1045,7 @@ class AsyncClient:
         self,
         method: str,
         url: str,
-        content: bytes | bytearray | list[int] | None = None,
+        content: bytes | bytearray | list[int] | Iterator[bytes] | AsyncIterator[bytes] | None = None,
         data: dict[str, str] | None = None,
         headers: dict[str, str] | None = None,
         timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1078,7 +1078,7 @@ class AsyncClient:
 def stream(
     method: str,
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1111,7 +1111,7 @@ def stream(
 
 def get(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1144,7 +1144,7 @@ def get(
 
 def post(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1177,7 +1177,7 @@ def post(
 
 def put(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1210,7 +1210,7 @@ def put(
 
 def patch(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1243,7 +1243,7 @@ def patch(
 
 def delete(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1276,7 +1276,7 @@ def delete(
 
 def head(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1309,7 +1309,7 @@ def head(
 
 def options(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
@@ -1339,7 +1339,7 @@ def options(
 
 def trace(
     url: str,
-    content: bytes | bytearray | list[int] | None = None,
+    content: bytes | bytearray | list[int] | Iterator[bytes] | None = None,
     data: dict[str, str] | None = None,
     headers: dict[str, str] | None = None,
     timeout: float | str | None = USE_CLIENT_DEFAULT,
diff --git a/impit-python/src/async_client.rs b/impit-python/src/async_client.rs
index 8963371a..40cde55f 100644
--- a/impit-python/src/async_client.rs
+++ b/impit-python/src/async_client.rs
@@ -11,7 +11,10 @@ use pyo3::{exceptions::PyTypeError, ffi::c_str, prelude::*};
 use crate::{
     cookies::PythonCookieJar,
     errors::ImpitPyError,
-    request::{form_to_bytes, parse_timeout, RequestBody, USE_CLIENT_DEFAULT_SENTINEL},
+    request::{
+        async_iterator_to_bytes, form_to_bytes, iterator_to_bytes, parse_timeout, RequestBody,
+        USE_CLIENT_DEFAULT_SENTINEL,
+    },
     response::ImpitPyResponse,
 };
 
@@ -135,7 +138,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -159,7 +162,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -183,7 +186,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -207,7 +210,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -231,7 +234,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -255,7 +258,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -279,7 +282,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -303,7 +306,7 @@ impl AsyncClient {
         &self,
         py: Python<'python>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -328,7 +331,7 @@ impl AsyncClient {
         py: Python<'python>,
         method: &str,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -374,35 +377,34 @@ impl AsyncClient {
         py: Python<'python>,
         method: &str,
         url: String,
-        content: Option<Vec<u8>>,
-        mut data: Option<RequestBody>,
+        content: Option<RequestBody<'_>>,
+        data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
         force_http3: Option<bool>,
         stream: Option<bool>,
     ) -> Result<pyo3::Bound<'python, PyAny>, PyErr> {
         let mut headers = headers.clone();
-
-        if let Some(content) = content {
-            data = Some(RequestBody::Bytes(content));
-        }
-
-        let body: Vec<u8> = match data {
-            Some(data) => match data {
-                RequestBody::Bytes(bytes) => Ok(bytes),
-                RequestBody::Form(form) => {
-                    headers.get_or_insert_with(HashMap::new).insert(
-                        "Content-Type".to_string(),
-                        "application/x-www-form-urlencoded".to_string(),
-                    );
-                    Ok(form_to_bytes(form))
-                }
-                RequestBody::CatchAll(e) => Err(PyErr::new::<PyTypeError, _>(format!(
+        let data = content.or(data);
+
+        let (async_body, body): (Option<Py<PyAny>>, Vec<u8>) = match data {
+            Some(RequestBody::AsyncIterator(iter)) => (Some(iter.0), Vec::new()),
+            Some(RequestBody::Bytes(bytes)) => (None, bytes),
+            Some(RequestBody::Iterator(iter)) => (None, iterator_to_bytes(iter)?),
+            Some(RequestBody::Form(form)) => {
+                headers.get_or_insert_with(HashMap::new).insert(
+                    "Content-Type".to_string(),
+                    "application/x-www-form-urlencoded".to_string(),
+                );
+                (None, form_to_bytes(form))
+            }
+            Some(RequestBody::CatchAll(e)) => {
+                return Err(PyErr::new::<PyTypeError, _>(format!(
                     "Unsupported data type in request body: {e:#?}"
-                ))),
-            },
-            None => Ok(Vec::new()),
-        }?;
+                )));
+            }
+            None => (None, Vec::new()),
+        };
 
         let timeout = parse_timeout(timeout)?;
 
@@ -422,6 +424,11 @@ impl AsyncClient {
         let impit = Arc::clone(&self.impit);
 
         pyo3_async_runtimes::tokio::future_into_py::<_, ImpitPyResponse>(py, async move {
+            let body = match async_body {
+                Some(iter) => async_iterator_to_bytes(iter).await?,
+                None => body,
+            };
+
             let response = match method_str.to_lowercase().as_str() {
                 "get" => impit.get(url, Some(body), Some(options)).await,
                 "post" => impit.post(url, Some(body), Some(options)).await,
diff --git a/impit-python/src/client.rs b/impit-python/src/client.rs
index a817cbfe..d5409cb5 100644
--- a/impit-python/src/client.rs
+++ b/impit-python/src/client.rs
@@ -11,7 +11,9 @@ use pyo3::{ffi::c_str, prelude::*};
 use crate::{
     cookies::PythonCookieJar,
     errors::ImpitPyError,
-    request::{form_to_bytes, parse_timeout, RequestBody, USE_CLIENT_DEFAULT_SENTINEL},
+    request::{
+        form_to_bytes, iterator_to_bytes, parse_timeout, RequestBody, USE_CLIENT_DEFAULT_SENTINEL,
+    },
     response::{self, ImpitPyResponse},
 };
 
@@ -132,7 +134,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -156,7 +158,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -180,7 +182,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -204,7 +206,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -228,7 +230,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -252,7 +254,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -276,7 +278,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -300,7 +302,7 @@ impl Client {
         &self,
         py: Python<'_>,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -325,7 +327,7 @@ impl Client {
         py: Python<'python>,
         method: &str,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
@@ -371,22 +373,25 @@ impl Client {
         py: Python<'_>,
         method: &str,
         url: String,
-        content: Option<Vec<u8>>,
-        mut data: Option<RequestBody>,
+        content: Option<RequestBody<'_>>,
+        data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
         force_http3: Option<bool>,
         stream: Option<bool>,
     ) -> Result<ImpitPyResponse, ImpitPyError> {
         let mut headers = headers.clone();
-
-        if let Some(content) = content {
-            data = Some(RequestBody::Bytes(content));
-        }
+        let data = content.or(data);
 
         let body: Vec<u8> = match data {
             Some(data) => match data {
+                RequestBody::AsyncIterator(_) => Err(ImpitPyError(ImpitError::BindingPassthroughError(
+                    "async iterators are not supported by the synchronous Client; use AsyncClient instead"
+                        .to_string(),
+                ))),
                 RequestBody::Bytes(bytes) => Ok(bytes),
+                RequestBody::Iterator(iter) => iterator_to_bytes(iter)
+                    .map_err(|e| ImpitPyError(ImpitError::BindingPassthroughError(e.to_string()))),
                 RequestBody::Form(form) => {
                     headers.get_or_insert_with(HashMap::new).insert(
                         "Content-Type".to_string(),
diff --git a/impit-python/src/lib.rs b/impit-python/src/lib.rs
index 9e16af38..4beb4dee 100644
--- a/impit-python/src/lib.rs
+++ b/impit-python/src/lib.rs
@@ -93,7 +93,7 @@ fn impit(_py: Python, m: &Bound<'_, PyModule>) -> PyResult<()> {
             fn $name(
                 _py: Python,
                 url: String,
-                content: Option<Vec<u8>>,
+                content: Option<RequestBody<'_>>,
                 data: Option<RequestBody>,
                 headers: Option<HashMap<String, String>>,
                 timeout: Option<Either<f64, &str>>,
@@ -122,7 +122,7 @@ fn impit(_py: Python, m: &Bound<'_, PyModule>) -> PyResult<()> {
         _py: Python<'python>,
         method: &str,
         url: String,
-        content: Option<Vec<u8>>,
+        content: Option<RequestBody<'_>>,
         data: Option<RequestBody>,
         headers: Option<HashMap<String, String>>,
         timeout: Option<Either<f64, &str>>,
diff --git a/impit-python/src/request.rs b/impit-python/src/request.rs
index 07a26da6..f50fe9e7 100644
--- a/impit-python/src/request.rs
+++ b/impit-python/src/request.rs
@@ -33,10 +33,34 @@ pub(crate) fn parse_timeout(
     }
 }
 
-use pyo3::FromPyObject;
+use pyo3::exceptions::{PyStopAsyncIteration, PyTypeError};
+use pyo3::types::{PyAnyMethods, PyIterator};
+use pyo3::{Borrowed, BoundObject, FromPyObject, Py, PyErr, PyResult, Python};
+
+/// Wraps a Python object that implements `__anext__`. Extraction only checks for the attribute
+/// (no side effects), unlike `Vec<u8>`/`PyIterator` extraction which can consume items.
+pub(crate) struct PyAsyncIterator(pub Py<PyAny>);
+
+impl<'a, 'py> FromPyObject<'a, 'py> for PyAsyncIterator {
+    type Error = PyErr;
+
+    fn extract(obj: Borrowed<'a, 'py, PyAny>) -> Result<Self, PyErr> {
+        if obj.hasattr("__anext__")? {
+            Ok(PyAsyncIterator(BoundObject::unbind(obj)))
+        } else {
+            Err(PyTypeError::new_err("object is not an async iterator"))
+        }
+    }
+}
 
 #[derive(FromPyObject)]
 pub(crate) enum RequestBody<'py> {
+    #[pyo3(transparent, annotation = "AsyncIterator[bytes]")]
+    AsyncIterator(PyAsyncIterator),
+    // Placed before `Bytes` because `Vec<u8>` extraction would otherwise partially consume the
+    // iterator while trying (and failing) to coerce its items into bytes.
+    #[pyo3(transparent, annotation = "Iterator[bytes]")]
+    Iterator(Bound<'py, PyIterator>),
     #[pyo3(transparent, annotation = "bytes")]
     Bytes(Vec<u8>),
     #[pyo3(transparent, annotation = "dict[str, str]")]
@@ -45,6 +69,37 @@ pub(crate) enum RequestBody<'py> {
     CatchAll(Bound<'py, PyAny>), // This extraction never fails
 }
 
+pub fn iterator_to_bytes(iter: Bound<'_, PyIterator>) -> PyResult<Vec<u8>> {
+    let mut body = Vec::new();
+    for chunk in iter {
+        body.extend(chunk?.extract::<Vec<u8>>()?);
+    }
+    Ok(body)
+}
+
+/// Drains a Python async iterator by repeatedly awaiting `__anext__`, until it raises
+/// `StopAsyncIteration`.
+pub async fn async_iterator_to_bytes(iter: Py<PyAny>) -> PyResult<Vec<u8>> {
+    let mut body = Vec::new();
+    loop {
+        let next = Python::attach(|py| {
+            pyo3_async_runtimes::tokio::into_future(
+                iter.call_method0(py, "__anext__")?.into_bound(py),
+            )
+        })?;
+
+        match next.await {
+            Ok(chunk) => {
+                body.extend(Python::attach(|py| chunk.extract::<Vec<u8>>(py))?);
+            }
+            Err(err) if Python::attach(|py| err.is_instance_of::<PyStopAsyncIteration>(py)) => {
+                return Ok(body);
+            }
+            Err(err) => return Err(err),
+        }
+    }
+}
+
 pub fn form_to_bytes(data: HashMap<String, String>) -> Vec<u8> {
     let mut body = Vec::new();
     for (key, value) in data {
diff --git a/impit-python/test/async_client_test.py b/impit-python/test/async_client_test.py
index b062e305..457eaf48 100644
--- a/impit-python/test/async_client_test.py
+++ b/impit-python/test/async_client_test.py
@@ -2,6 +2,7 @@
 import json
 import socket
 import threading
+from collections.abc import AsyncIterator
 from http.cookiejar import Cookie, CookieJar
 from typing import Literal
 
@@ -582,6 +583,26 @@ async def test_passing_binary_body(self, browser: Browser) -> None:
         assert response.status_code == 200
         assert json.loads(response.text)['data'] == 'Impit-Test:foořžš'
 
+    @pytest.mark.asyncio
+    async def test_passing_generator_body(self, browser: Browser) -> None:
+        impit = AsyncClient(browser=browser)
+
+        response = await impit.post(get_httpbin_url('/post'), content=(chunk for chunk in [b'foo', b'bar']))
+        assert response.status_code == 200
+        assert json.loads(response.text)['data'] == 'foobar'
+
+    @pytest.mark.asyncio
+    async def test_passing_async_generator_body(self, browser: Browser) -> None:
+        impit = AsyncClient(browser=browser)
+
+        async def agen() -> AsyncIterator[bytes]:
+            yield b'foo'
+            yield b'bar'
+
+        response = await impit.post(get_httpbin_url('/post'), content=agen())
+        assert response.status_code == 200
+        assert json.loads(response.text)['data'] == 'foobar'
+
     @pytest.mark.parametrize(
         ('method'),
         ['POST', 'PUT', 'PATCH'],
diff --git a/impit-python/test/basic_client_test.py b/impit-python/test/basic_client_test.py
index f78bffe6..bcda2c04 100644
--- a/impit-python/test/basic_client_test.py
+++ b/impit-python/test/basic_client_test.py
@@ -2,6 +2,7 @@
 import socket
 import threading
 import time
+from collections.abc import AsyncIterator, Iterator
 from http.cookiejar import Cookie, CookieJar
 from typing import Literal
 
@@ -13,6 +14,7 @@
     Client,
     ConnectTimeout,
     Cookies,
+    HTTPError,
     ReadTimeout,
     RemoteProtocolError,
     StreamClosed,
@@ -507,6 +509,26 @@ def test_passing_binary_body(self, browser: Browser) -> None:
         assert response.status_code == 200
         assert response.json()['data'] == 'Impit-Test:foořžš'
 
+    def test_passing_generator_body(self, browser: Browser) -> None:
+        impit = Client(browser=browser)
+
+        def gen() -> Iterator[bytes]:
+            yield b'Impit-'
+            yield b'Test'
+
+        response = impit.post(get_httpbin_url('/post'), content=gen())
+        assert response.status_code == 200
+        assert response.json()['data'] == 'Impit-Test'
+
+    def test_passing_async_generator_body_raises(self, browser: Browser) -> None:
+        impit = Client(browser=browser)
+
+        async def agen() -> AsyncIterator[bytes]:
+            yield b'foo'
+
+        with pytest.raises(HTTPError):
+            impit.post(get_httpbin_url('/post'), content=agen())  # type: ignore[arg-type]
+
     @pytest.mark.parametrize(
         ('method'),
         ['POST', 'PUT', 'PATCH'],
@@ -520,6 +542,20 @@ def test_methods_accept_request_body(self, browser: Browser, method: str) -> Non
         assert response.status_code == 200
         assert response.json()['data'] == 'foo'
 
+    def test_methods_accept_generator_body(self, browser: Browser) -> None:
+        impit = Client(browser=browser)
+
+        response = impit.post(get_httpbin_url('/post'), content=(chunk for chunk in [b'foo', b'bar']))
+        assert response.status_code == 200
+        assert response.json()['data'] == 'foobar'
+
+    def test_passing_iterator_body(self, browser: Browser) -> None:
+        impit = Client(browser=browser)
+
+        response = impit.post(get_httpbin_url('/post'), content=iter([b'foo', b'bar']))
+        assert response.status_code == 200
+        assert response.json()['data'] == 'foobar'
+
     def test_content(self, browser: Browser) -> None:
         impit = Client(browser=browser)
 
diff --git a/impit-python/test/no_client_test.py b/impit-python/test/no_client_test.py
index 6090b976..3234e331 100644
--- a/impit-python/test/no_client_test.py
+++ b/impit-python/test/no_client_test.py
@@ -365,6 +365,11 @@ def test_passing_binary_body(self) -> None:
         assert response.status_code == 200
         assert response.json()['data'] == 'Impit-Test:foořžš'
 
+    def test_passing_generator_body(self) -> None:
+        response = impit.post(get_httpbin_url('/post'), content=(chunk for chunk in [b'foo', b'bar']))
+        assert response.status_code == 200
+        assert response.json()['data'] == 'foobar'
+
     @pytest.mark.parametrize(
         ('method'),
         ['POST', 'PUT', 'PATCH'],