diff --git a/.github/workflows/Changelog.yml b/.github/workflows/Changelog.yml
new file mode 100644
index 0000000..9de6c31
--- /dev/null
+++ b/.github/workflows/Changelog.yml
@@ -0,0 +1,21 @@
+name: Check Changelog
+
+on: pull_request
+
+jobs:
+  changelog:
+    runs-on: ubuntu-latest
+    name: Changelog should be updated
+    strategy:
+      fail-fast: false
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 2
+
+      - name: Git fetch
+        run: git fetch
+
+      - name: Check that changelog has been updated.
+        run: git diff --exit-code origin/${{ github.base_ref }} -- CHANGELOG.md && exit 1 || exit 0
diff --git a/.github/workflows/Version_Check.yml b/.github/workflows/Version_Check.yml
new file mode 100644
index 0000000..d0387ab
--- /dev/null
+++ b/.github/workflows/Version_Check.yml
@@ -0,0 +1,39 @@
+name: Check pyproject.toml Version Change
+
+on:
+  pull_request:
+    branches:
+      - 'main'
+
+jobs:
+  check-version:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Get current version in PR branch
+        id: get-pr-version
+        run: |
+          PR_VERSION=$(sed -n -e 's/^version = "\(.*\)"/\1/p' pyproject.toml)
+          echo "PR_VERSION=$PR_VERSION" >> $GITHUB_ENV
+
+      - name: Get version in base branch
+        id: get-base-version
+        run: |
+          git fetch origin ${{ github.event.pull_request.base.ref }}
+          git checkout FETCH_HEAD
+          BASE_VERSION=$(sed -n -e 's/^version = "\(.*\)"/\1/p' pyproject.toml)
+          echo "BASE_VERSION=$BASE_VERSION" >> $GITHUB_ENV
+
+      - name: Compare versions
+        run: |
+          echo "PR version: ${{ env.PR_VERSION }}"
+          echo "Base branch version: ${{ env.BASE_VERSION }}"
+
+          if [ "${{ env.PR_VERSION }}" == "${{ env.BASE_VERSION }}" ]; then
+            echo "Version number has not been changed."
+            exit 1
+          else
+            echo "Version number has changed."
+          fi
diff --git a/.github/workflows/pr.yml b/.github/workflows/linting.yml
similarity index 100%
rename from .github/workflows/pr.yml
rename to .github/workflows/linting.yml
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..abad543
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,21 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- Changelog!
+- PR workflows.
+- Version number in UI.
+
+## [0.0.1]
+
+- Initial release
+
+[Unreleased]: https://github.com/itk-dev-rpa/OpenPostbud/compare/0.0.1...HEAD
+[0.0.1]: https://github.com/itk-dev-rpa/OpenPostbud/releases/tag/0.0.1
diff --git a/src/OpenPostbud/config.py b/src/OpenPostbud/config.py
index df3d55a..490f1ee 100644
--- a/src/OpenPostbud/config.py
+++ b/src/OpenPostbud/config.py
@@ -5,6 +5,7 @@
 import os
 import logging
 import json
+from importlib import metadata
 
 import dotenv
 
@@ -49,6 +50,8 @@ def format(self, record: logging.LogRecord):
 SHIPMENT_LIFETIME_DAYS = int(os.environ['shipment_lifetime_days'])
 REGISTRATION_JOB_LIFETIME_DAYS = int(os.environ['registration_job_lifetime_days'])
 
+OPENPOSTBUD_VERSION = metadata.version("OpenPostbud")
+
 # Workers
 CVR = os.environ['cvr']
 KOMBIT_CERT_PATH = os.environ['kombit_cert_path']
diff --git a/src/OpenPostbud/ui_components.py b/src/OpenPostbud/ui_components.py
index e34e788..ecbab11 100644
--- a/src/OpenPostbud/ui_components.py
+++ b/src/OpenPostbud/ui_components.py
@@ -7,6 +7,7 @@
 from nicegui import ui, app
 
 from OpenPostbud.middleware import authentication
+from OpenPostbud import config
 
 
 def header():
@@ -32,6 +33,8 @@ def header():
         ui.space()
         ui.label(authentication.get_current_user()).classes('text-lg text-white')
         ui.label(str(authentication.get_current_user_roles())).classes('text-lg text-white')
+        ui.separator().props("vertical color=white size=2px")
+        ui.label(config.OPENPOSTBUD_VERSION).classes('text-lg text-white')
         ui.button("Log Ud", on_click=authentication.logout, color="white").classes("text-primary")