diff --git a/stellar-payment-platform/middleware/correlation.js b/stellar-payment-platform/middleware/correlation.js
new file mode 100644
index 0000000..3e45be7
--- /dev/null
+++ b/stellar-payment-platform/middleware/correlation.js
@@ -0,0 +1,25 @@
+const { v4: uuidv4 } = require('uuid');
+
+const CORRELATION_HEADER = 'X-Correlation-ID';
+
+// #31 — Correlation ID middleware for end-to-end request tracing.
+// Reuses an incoming X-Correlation-ID header when present, otherwise generates
+// a fresh uuidv4. The ID is exposed on req.correlationId and echoed back on the
+// response so callers and downstream services can stitch logs together.
+const correlationId = (req, res, next) => {
+  const incoming = req.get(CORRELATION_HEADER);
+  const id = typeof incoming === 'string' && incoming.trim() ? incoming.trim() : uuidv4();
+
+  req.correlationId = id;
+  res.set(CORRELATION_HEADER, id);
+
+  // Prefix request logs with the correlation ID so a single API call can be
+  // traced end-to-end across the backend's log output.
+  res.on('finish', () => {
+    console.log(`[Correlation ID: ${id}] ${req.method} ${req.originalUrl} ${res.statusCode}`);
+  });
+
+  next();
+};
+
+module.exports = { correlationId, CORRELATION_HEADER };
diff --git a/stellar-payment-platform/package-lock.json b/stellar-payment-platform/package-lock.json
index 6667cba..4fe347d 100644
--- a/stellar-payment-platform/package-lock.json
+++ b/stellar-payment-platform/package-lock.json
@@ -25,6 +25,7 @@
         "rate-limit-redis": "^4.2.0",
         "redis": "^4.7.0",
         "sqlite3": "^5.1.7",
+        "uuid": "^9.0.1",
         "xss": "^1.0.15"
       },
       "devDependencies": {
@@ -64,7 +65,6 @@
       "integrity": "sha512-RgHBCvtjbOK2gXSNBNIkNoEc9qoVEtau3hj8gEqKQuL3HZAibKarWFEI3Lfm6EYKkLalOh8eSrj9b+ch9H/VBA==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "@babel/code-frame": "^7.29.7",
         "@babel/generator": "^7.29.7",
@@ -1154,7 +1154,6 @@
       "resolved": "https://registry.npmjs.org/@redis/client/-/client-1.6.1.tgz",
       "integrity": "sha512-/KCsg3xSlR+nCK8/8ZYSknYxvXHwubJrU82F3Lm1Fp6789VQ0/3RJKfsmRXjqfaTA++23CvC3hqmqe/2GEt6Kw==",
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "cluster-key-slot": "1.1.2",
         "generic-pool": "3.9.0",
@@ -1962,7 +1961,6 @@
         }
       ],
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "baseline-browser-mapping": "^2.10.38",
         "caniuse-lite": "^1.0.30001799",
@@ -3248,7 +3246,6 @@
       "resolved": "https://registry.npmjs.org/express/-/express-4.22.2.tgz",
       "integrity": "sha512-IuL+Elrou2ZvCFHs18/CIzy2Nzvo25nZ1/D2eIZlz7c+QUayAcYoiM2BthCjs+EBHVpjYjcuLDAiCWgeIX3X1Q==",
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "accepts": "~1.3.8",
         "array-flatten": "1.1.1",
@@ -3295,7 +3292,6 @@
       "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-7.5.1.tgz",
       "integrity": "sha512-7iN8iPMDzOMHPUYllBEsQdWVB6fPDMPqwjBaFrgr4Jgr/+okjvzAy+UHlYYL/Vs0OsOrMkwS6PJDkFlJwoxUnw==",
       "license": "MIT",
-      "peer": true,
       "engines": {
         "node": ">= 16"
       },
@@ -6256,7 +6252,6 @@
       "devOptional": true,
       "hasInstallScript": true,
       "license": "Apache-2.0",
-      "peer": true,
       "dependencies": {
         "@prisma/config": "6.19.3",
         "@prisma/engines": "6.19.3"
@@ -7597,6 +7592,20 @@
         "node": ">= 0.4.0"
       }
     },
+    "node_modules/uuid": {
+      "version": "9.0.1",
+      "resolved": "https://registry.npmjs.org/uuid/-/uuid-9.0.1.tgz",
+      "integrity": "sha512-b+1eJOlsR9K8HJpow9Ok3fiWOWSIcIzXodvv0rQjVoOVNpWMpxf1wZNpt4y9h10odCNrqnYp1OBzRktckBe3sA==",
+      "deprecated": "uuid@10 and below is no longer supported.  For ESM codebases, update to uuid@latest.  For CommonJS codebases, use uuid@11 (but be aware this version will likely be deprecated in 2028).",
+      "funding": [
+        "https://github.com/sponsors/broofa",
+        "https://github.com/sponsors/ctavan"
+      ],
+      "license": "MIT",
+      "bin": {
+        "uuid": "dist/bin/uuid"
+      }
+    },
     "node_modules/v8-to-istanbul": {
       "version": "9.3.0",
       "resolved": "https://registry.npmjs.org/v8-to-istanbul/-/v8-to-istanbul-9.3.0.tgz",
diff --git a/stellar-payment-platform/package.json b/stellar-payment-platform/package.json
index 4b5f5ac..acb49fe 100644
--- a/stellar-payment-platform/package.json
+++ b/stellar-payment-platform/package.json
@@ -36,6 +36,7 @@
     "rate-limit-redis": "^4.2.0",
     "redis": "^4.7.0",
     "sqlite3": "^5.1.7",
+    "uuid": "^9.0.1",
     "xss": "^1.0.15"
   },
   "devDependencies": {
diff --git a/stellar-payment-platform/server.js b/stellar-payment-platform/server.js
index 618fbc0..2c141d9 100644
--- a/stellar-payment-platform/server.js
+++ b/stellar-payment-platform/server.js
@@ -6,6 +6,7 @@ const RedisStore = require('rate-limit-redis');
 const { createClient } = require('redis');
 const { prisma } = require('./prismaClient');
 const { scheduleCleanupJob } = require('./src/cleanup-cron');
+const { correlationId } = require('./middleware/correlation');
 const Filter = require('bad-words');
 const dotenv = require('dotenv');
 const timeout = require('connect-timeout');
@@ -50,6 +51,9 @@ const corsOptions = {
   optionsSuccessStatus: 204,
 };
 
+// #31 — Attach a correlation ID to every request before anything else runs so
+// all downstream middleware, handlers and logs can reference the same trace.
+app.use(correlationId);
 const redisClient = process.env.REDIS_URL ? createClient({
   url: process.env.REDIS_URL
 }) : null;
@@ -522,11 +526,14 @@ app.use((err, _req, res, _next) => {
 
   if (statusCode === 500) {
     const errorId = crypto.randomUUID();
-    console.error(`[Error ID: ${errorId}]`, err);
+    // #31 — Prefix error logs with the correlation ID so a single API call can
+    // be traced across every log line it produced.
+    console.error(`[Correlation ID: ${req.correlationId}] [Error ID: ${errorId}]`, err);
     return res.status(500).json({
       success: false,
       error: 'Internal Server Error',
       reference_id: errorId,
+      correlation_id: req.correlationId
     });
   }