diff --git a/draft-release/README.md b/draft-release/README.md
new file mode 100644
index 0000000..35a7417
--- /dev/null
+++ b/draft-release/README.md
@@ -0,0 +1,132 @@
+# Draft Release - a Shared Global Release Engine
+
+Composite [action](action.yaml) that generates categorised draft release notes
+from merged pull requests and updates (or creates) a draft GitHub Release for
+the current tag.
+
+## Location
+
+This action is intentionally located at repository root level and has the
+following components:
+
+- `draft-release/action.yaml` (composite action)
+- `draft-release/bin/compile-release-notes.sh` (compiler script)
+- `draft-release/templates/release.yml` (release category template)
+- `draft-release/README.md` (this document)
+
+The changelog template source of truth is `draft-release/templates/release.yml`.
+
+## Changelog Categories for Simulation Systems
+
+Pull Requests are evaluated against all categories from **top to bottom**. If a
+PR has multiple labels matching different categories, it will appear in **all
+matching categories**. This allows a single PR to be listed in multiple sections
+for comprehensive changelog organisation.
+
+| Category | Labels | Example |
+| -------- | ------ | ------- |
+| 💥 Breaking Changes | `breaking-change` | Critical infrastructure changes, breaking adjustments, or API removals. |
+| 📦 Dependency Updates | `dependency` | Updates to third-party dependencies, including security patches. |
+| ⚠️ Deprecations | `deprecated` | Features or APIs that are being phased out, but still functional. |
+| 🐛 Bug Fixes | `bugfix` | Code corrections or hotfixes resolving functional issues. |
+| ✨ New Features | `feature` | Customer-facing features, enhancements, or structural additions. |
+| 🔬 Scientific & Algorithmic Updates | `science`, `technical` | **science**: Domain-specific mathematical changes or model updates.<br>**technical**: Deep algorithmic optimisations or background logic shifts. |
+| 📚 Documentation | `documentation` | Changes isolated to READMEs, inline code docstrings, scientific documentation, working practices, or other non-functional documentation updates. |
+| ⚡ Performance Improvements | `optimisation` | Direct speed execution metrics, runtime improvements, memory, storage, or other resource optimisations. |
+| ♻️ Refactoring | `refactor` | Code cleanup, modularisation, or other internal improvements without behavior changes. |
+| 🛠️ Maintenance | `build`, `chore`, `ci` | **build**: Changes affecting build tools or external compiler toolchains.<br>**chore**: General housekeeping, licence updates, or minor administrative tasks.<br>**ci**: Changes to GitHub Actions workflows, CI/CD pipelines, or other automation.|
+
+> [!NOTE]
+> First time contributors are added automatically when the merged PR has an
+> `author_association` of `FIRST_TIME_CONTRIBUTOR`.
+
+### Excluded Labels
+
+PRs carrying any of the following labels are **hidden** from the changelog
+output entirely, regardless of any other labels they carry:
+
+| Label | Purpose |
+| ----- | ------- |
+| `ignore-changelog` | Escape-hatch label to manually suppress a specific PR from the logs. |
+| `test` | Changes related to testing frameworks or test cases. |
+| `wip` | Work in progress PRs that are not ready for release. |
+
+## How It Works
+
+1. Checks out the caller repository into `local-code` with full tag history.
+2. Runs `draft-release/bin/compile-release-notes.sh` to:
+    - find release commits,
+    - map merged PRs to changelog categories from
+      `draft-release/templates/release.yml`,
+    - write `release-notes.md` and set `has_commits` output.
+3. If commits exist, creates or updates a draft release for the current tag.
+
+```mermaid
+graph TD
+    %% Define Node Styles for Scannability
+    classDef trigger style fill:#f9f,stroke:#333,stroke-width:2px,font-weight:bold;
+    classDef step style fill:#bbf,stroke:#333,stroke-width:1px;
+    classDef desc style fill:#fff,stroke:#666,stroke-width:1px,stroke-dasharray: 5 5,font-size:12px;
+
+    %% Workflow Connections
+    Trigger([Tag Push Event]) --> Step1[1. Checkout Caller Repository]
+    Step1 --> Step2[2. Compile Release Notes]
+    Step2 --> Step3{Has Merged PRs?}
+    Step3 -->|Yes| Step4[3. Create or Update Draft Release]
+    Step3 -->|No| Skip[Skip Release Creation]
+
+    %% Step Explanations (Side-nodes)
+    Step1 -.-> Desc1[Checks out the calling repository into <code>local-code</code><br>with full history and tags]
+    Step2 -.-> Desc2[Executes <code>compile-release-notes.sh</code><br>using action-local template <code>release.yml</code>]
+    Step4 -.-> Desc3[Executes <code>gh release create/edit</code><br>with categorised changelog notes in draft state]
+    Skip -.-> Desc4[Workflow completes early<br>if no merged PRs found in release window]
+
+    %% Assign Classes to Nodes
+    class Trigger trigger;
+    class Step1,Step2,Step3,Step4,Skip step;
+    class Desc1,Desc2,Desc3,Desc4 desc;
+```
+
+## Usage
+
+```yaml
+name: Automated Release Notes
+
+on:
+  push:
+    tags:
+      - "v*"
+
+jobs:
+  release:
+    runs-on: ubuntu-slim
+    permissions:
+      contents: write
+      pull-requests: read
+    steps:
+      - name: Draft Release
+        uses: MetOffice/growss/draft-release@main  # or tag or sha
+```
+
+## Required Permissions
+
+- `contents: write` to create/edit draft releases.
+- `pull-requests: read` to read merged PR metadata for changelog generation.
+
+## Outputs
+
+The compile step exposes:
+
+- `has_commits`: `true` when release notes were generated from commits,
+  otherwise `false`.
+
+## Notes
+
+- The action uses `${{ github.token }}` internally for `gh` API commands.
+- `release-notes.md` is generated in the GitHub Actions workspace root.
+- The release body is grouped by labels defined in
+  `draft-release/templates/release.yml`.
+
+## Licence
+
+&copy; Crown copyright Met Office. See [LICENCE](../LICENCE) file for details.
diff --git a/draft-release/action.yaml b/draft-release/action.yaml
new file mode 100644
index 0000000..c8e05f1
--- /dev/null
+++ b/draft-release/action.yaml
@@ -0,0 +1,49 @@
+# ------------------------------------------------------------------------------
+# (c) Crown copyright Met Office. All rights reserved.
+# The file LICENCE, distributed with this code, contains details of the terms
+# under which the code may be used.
+# ------------------------------------------------------------------------------
+
+name: Shared Global Release Engine
+description: Automates draft releases using centralised assets
+
+runs:
+  using: "composite"
+  steps:
+    - name: Checkout caller repository with full history
+      uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+      with:
+        path: local-code
+        fetch-depth: 0
+        fetch-tags: true
+        persist-credentials: false
+
+    - name: Compile categorised release notes from template labels
+      id: compile-release-notes
+      shell: bash
+      env:
+        GH_TOKEN: ${{ github.token }}
+        CALLER_REPO: ${{ github.repository }}
+        GITHUB_REF_NAME: ${{ github.ref_name }}
+        GITHUB_SHA: ${{ github.sha }}
+      run: |
+        set -euo pipefail
+        bash "${{ github.action_path }}/bin/compile-release-notes.sh" \
+          "$CALLER_REPO" "$GITHUB_SHA" "$GITHUB_REF_NAME"
+
+    - if: steps.compile-release-notes.outputs.has_commits == 'true'
+      shell: bash
+      working-directory: local-code
+      env:
+        GH_TOKEN: ${{ github.token }}
+        GITHUB_REF_NAME: ${{ github.ref_name }}
+      run: |
+        set -euo pipefail
+        TITLE="Release ${GITHUB_REF_NAME} (Draft)"
+        if gh release view "${GITHUB_REF_NAME}" >/dev/null 2>&1; then
+          gh release edit "${GITHUB_REF_NAME}" --draft --title "${TITLE}"  \
+            --notes-file ../release-notes.md
+        else
+          gh release create "${GITHUB_REF_NAME}" --draft --title "${TITLE}" \
+            --notes-file ../release-notes.md
+        fi
diff --git a/draft-release/bin/compile-release-notes.sh b/draft-release/bin/compile-release-notes.sh
new file mode 100644
index 0000000..79f5449
--- /dev/null
+++ b/draft-release/bin/compile-release-notes.sh
@@ -0,0 +1,259 @@
+#!/usr/bin/env bash
+# ------------------------------------------------------------------------------
+# (c) Crown copyright Met Office. All rights reserved.
+# The file LICENCE, distributed with this code, contains details of the terms
+# under which the code may be used.
+# ------------------------------------------------------------------------------
+# Compile categorised release notes from a shared changelog template.
+# Helper script for the draft-release GitHub Action workflow.
+#
+# Usage:
+#   compile-release-notes.sh <caller_repo> <github_sha> <github_ref_name>
+#
+# <caller_repo>      - External repository that called this workflow
+# <github_sha>       - SHA of checkout in local-code (Caller repository) for which to generate release notes
+# <github_ref_name>  - refs/tags/v1.0.0, refs/heads/main, or a specific commit SHA
+# Required environment:
+#   GH_TOKEN       - GitHub token for API access
+#   GITHUB_OUTPUT  - Set automatically in GitHub Actions
+
+set -euo pipefail
+
+error_exit() {
+  echo "::error::$1" >&2
+  exit 1
+}
+
+[[ $# -lt 3 ]] && error_exit "Usage: $0 <caller_repo> <github_sha> <github_ref_name>"
+
+CALLER_REPO="$1"
+GITHUB_SHA="$2"
+GITHUB_REF_NAME="$3"
+TEMPLATE_REF="${TEMPLATE_REF:-unknown}"
+
+# Dynamically calculate the path relative to where this script lives on disk
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+TEMPLATE_FILE="$SCRIPT_DIR/../templates/release.yml"
+TEMPLATE_REPO="MetOffice/growss"
+TEMPLATE_PATH="draft-release/templates/release.yml"
+
+# Check for required commands and files
+command -v gh >/dev/null 2>&1 || error_exit "GitHub CLI (gh) is required but not available."
+command -v jq >/dev/null 2>&1 || error_exit "jq is required but not available."
+[[ -f "$TEMPLATE_FILE" ]] || error_exit "Template file not found: $TEMPLATE_FILE"
+
+# Determine previous tag from local-code git history
+# a. Get the most recent tag reachable from the commit before the current GITHUB_SHA.
+PREV_TAG="$(git -C local-code describe --tags --abbrev=0 "${GITHUB_SHA}^" 2>/dev/null || true)"
+# b. Get the latest tag starting with "v", excluding the current branch/tag name.
+# Sorts by creation date (newest first), takes the top result, and defaults to empty if none exist.
+PREV_TAG0="$(git -C local-code tag --list "v*" --sort=-creatordate | grep -v "^${GITHUB_REF_NAME}$" | head -n 1 || true)"
+
+# -- Debugging output ----------------------------------------------------------
+echo "**Caller Repository**:       ${CALLER_REPO}"
+echo "Current ref name:            ${GITHUB_REF_NAME}"
+echo "Current commit SHA:          ${GITHUB_SHA}"
+echo "Previous tag (v*):           ${PREV_TAG0:-None}"
+echo "Previous tag (git describe): ${PREV_TAG:-None}"
+echo "**Template Repository**:     ${TEMPLATE_REPO}"
+echo "Template ref (version):      ${TEMPLATE_REF}"
+echo "Template path:               ${TEMPLATE_PATH}"
+echo "Template file:               ${TEMPLATE_FILE}"
+# ------------------------------------------------------------------------------
+
+if [ -n "$PREV_TAG" ]; then
+  git -C local-code rev-list --max-count=300 "${PREV_TAG}..${GITHUB_SHA}" >commit-shas.txt
+else
+  git -C local-code rev-list --max-count=300 "${GITHUB_SHA}" >commit-shas.txt
+fi
+
+# If no commits were found, create a release notes file indicating this and exit early
+if [ ! -s commit-shas.txt ]; then
+  {
+    echo "## Changelog"
+    echo
+    echo "* No commits found for this release window."
+  } >release-notes.md
+  echo "has_commits=false" >>"${GITHUB_OUTPUT}"
+  echo "::warning::No commits found for this release window."
+  exit 0
+fi
+
+# Instead of iterating through commits, we pull the 200 most recent merged PRs,
+# (for all PRs use --paginate with single API call) then match them against
+# commit-shas.txt locally.
+{
+  gh api "repos/${CALLER_REPO}/pulls?state=closed&per_page=100&page=1"
+  gh api "repos/${CALLER_REPO}/pulls?state=closed&per_page=100&page=2"
+} | jq -r '.[] | select(.merged_at != null) |
+  "\(.merge_commit_sha) \(.number) \(.title) | \(.user.login) | \([.labels[].name] | join(",")) | \(.author_association)"' >recent-prs.txt
+
+# Filter recent-prs down to ONLY those matching a commit SHA from our release range
+awk 'NR==FNR { shas[tolower($1)]=1; next } (tolower($1) in shas) { print }' commit-shas.txt recent-prs.txt >pr-data.txt
+
+if [ ! -s pr-data.txt ]; then
+  {
+    echo "## Changelog"
+    echo
+    echo "* No pull requests found for this release window."
+  } >release-notes.md
+  echo "has_commits=false" >>"${GITHUB_OUTPUT}"
+  echo "::warning::No pull requests found for this release window."
+  exit 0
+fi
+
+# Parse template YAML (limited parser for current release.yml structure)
+declare -a CATEGORY_TITLES=()
+declare -a CATEGORY_LABELS=()
+declare -a EXCLUDE_LABELS=()
+
+mode=""
+in_category_labels=0
+current_index=-1
+
+while IFS= read -r raw_line; do
+  line="${raw_line%%#*}"
+  trimmed="${line#"${line%%[![:space:]]*}"}"
+  trimmed="${trimmed%"${trimmed##*[![:space:]]}"}"
+  [ -z "$trimmed" ] && continue
+
+  case "$trimmed" in
+    changelog:) continue ;;
+    categories: | exclude:)
+      mode="${trimmed%?}"
+      in_category_labels=0
+      continue
+      ;;
+    labels:)
+      case "$mode" in
+        categories) [ "$current_index" -ge 0 ] && in_category_labels=1 ;;
+        exclude) in_category_labels=2 ;;
+      esac
+      continue
+      ;;
+  esac
+
+  if [ "$mode" = "categories" ] && [[ "$trimmed" =~ ^-[[:space:]]title:[[:space:]]*\"(.*)\"$ ]]; then
+    CATEGORY_TITLES+=("${BASH_REMATCH[1]}")
+    CATEGORY_LABELS+=("")
+    current_index=$((current_index + 1))
+    in_category_labels=0
+    continue
+  fi
+
+  if [ "$in_category_labels" -eq 1 ] && [[ "$trimmed" =~ ^-[[:space:]]+\"?([A-Za-z0-9._-]+)\"?\;?$ ]]; then
+    lbl="${BASH_REMATCH[1],,}"
+    if [ -z "${CATEGORY_LABELS[$current_index]}" ]; then
+      CATEGORY_LABELS[current_index]="$lbl"
+    else
+      CATEGORY_LABELS[current_index]+="|$lbl"
+    fi
+    continue
+  fi
+
+  if [ "$in_category_labels" -eq 2 ] && [[ "$trimmed" =~ ^-[[:space:]]+\"?([A-Za-z0-9._-]+)\"?\;?$ ]]; then
+    EXCLUDE_LABELS+=("${BASH_REMATCH[1],,}")
+    continue
+  fi
+done <"$TEMPLATE_FILE"
+
+# Store PR lines in temporary files for each category, then concatenate them into the final release notes.
+tmp_dir="$(mktemp -d)"
+trap 'rm -rf "$tmp_dir"' EXIT
+
+for i in "${!CATEGORY_TITLES[@]}"; do : >"$tmp_dir/cat_${i}.md"; done
+: >"$tmp_dir/new_contributors.md"  # Create or clear file for new contributors
+
+# Read the local intersected PR file and map categories
+while IFS= read -r row || [ -n "$row" ]; do
+  [ -z "$row" ] && continue
+
+  # Row structure: <merge_sha> <pr_number> <title> | <user> | <labels> | <author_association>
+  # Uses ' [|] ' as a definitive delimiter anchor to safely handle titles containing literal '|' characters.
+  regex='^([^[:space:]]+)[[:space:]]+([0-9]+)[[:space:]]+(.*)[[:space:]]\|[[:space:]]+([^|]+)[[:space:]]+\|[[:space:]]*([^|]*)[[:space:]]*\|[[:space:]]*(.*)$'
+
+  if [[ "$row" =~ $regex ]]; then
+    _sha="${BASH_REMATCH[1]}"
+    pr="${BASH_REMATCH[2]}"
+    title="${BASH_REMATCH[3]}"
+    user="${BASH_REMATCH[4]}"
+    user=$(echo "$user" | xargs)
+    labels="${BASH_REMATCH[5]}"
+    labels=$(echo "$labels" | xargs)
+    association="${BASH_REMATCH[6]}"
+    association=$(echo "$association" | xargs)
+  else
+    echo "::warning::Row did not match expected format: $row"
+    continue
+  fi
+
+  # Map New Contributors,without relying on labels
+  if [ "$association" = "FIRST_TIME_CONTRIBUTOR" ]; then
+    if ! grep -q "@${user}" "$tmp_dir/new_contributors.md"; then
+      echo "* @${user} made their first contribution in #${pr}" >> "$tmp_dir/new_contributors.md"
+    fi
+  fi
+
+  # Convert labels to an array and normalize to lowercase
+  IFS=',' read -r -a label_array <<<"${labels,,}"
+
+  # Check exclude labels
+  skip=0
+  for ex in "${EXCLUDE_LABELS[@]}"; do
+    for lbl in "${label_array[@]}"; do
+      [ "$lbl" = "$ex" ] && {
+        skip=1
+        break 2  # Breaks out of both loops
+      }
+    done
+  done
+  [ "$skip" -eq 1 ] && continue
+
+  pr_line="1. ${title} (@${user}) in #${pr}"
+
+  for i in "${!CATEGORY_TITLES[@]}"; do
+    IFS='|' read -r -a cat_labels <<<"${CATEGORY_LABELS[$i]}"
+    matched_this_category=0
+    for cat_lbl in "${cat_labels[@]}"; do
+      for lbl in "${label_array[@]}"; do
+        if [ "$lbl" = "$cat_lbl" ]; then
+          # Only append once per category block, even if multiple labels match this group
+          if [ "$matched_this_category" -eq 0 ]; then
+            matched_this_category=1
+            echo "$pr_line" >>"$tmp_dir/cat_${i}.md"
+          fi
+          break # Breaks out of the PR labels loop; moves to next category label
+        fi
+      done
+    done
+  done
+done <pr-data.txt
+
+{
+  echo "## Key Changes"
+  echo
+  wrote_any=0
+  for i in "${!CATEGORY_TITLES[@]}"; do
+    if [ -s "$tmp_dir/cat_${i}.md" ]; then
+      wrote_any=1
+      echo "### ${CATEGORY_TITLES[$i]}"
+      cat "$tmp_dir/cat_${i}.md"
+      echo
+    fi
+  done
+
+  if [ -s "$tmp_dir/new_contributors.md" ]; then
+    wrote_any=1
+    echo "### New Contributors 🎉"
+    cat "$tmp_dir/new_contributors.md"
+  fi
+
+  [ "$wrote_any" -eq 0 ] && echo "* No pull requests matched release categories."
+  if [ -n "$PREV_TAG" ]; then
+    echo
+    echo "**Full Changelog**: https://github.com/${CALLER_REPO}/compare/${PREV_TAG}...${GITHUB_REF_NAME}"
+  fi
+} >release-notes.md
+
+echo "has_commits=true" >>"${GITHUB_OUTPUT}"
+echo "::notice::Draft release notes generated successfully."
diff --git a/draft-release/templates/release.yml b/draft-release/templates/release.yml
new file mode 100644
index 0000000..cd25bc3
--- /dev/null
+++ b/draft-release/templates/release.yml
@@ -0,0 +1,79 @@
+# ------------------------------------------------------------------------------
+# (c) Crown copyright Met Office. All rights reserved.
+# The file LICENCE, distributed with this code, contains details of the terms
+# under which the code may be used.
+# ------------------------------------------------------------------------------
+# Simulation Systems Release Changelog Configuration
+
+changelog:
+  # Categories are evaluated sequentially from top to bottom.
+  # If a PR has multiple matching labels, it will appear in all matching categories.
+
+  categories:
+    # (breaking-change) Critical infrastructure changes or API removals.
+    - title: "💥 Breaking Changes"
+      labels:
+        - "breaking-change"
+
+    # (dependency) Updates to third-party dependencies, including security patches.
+    - title: "📦 Dependency Updates"
+      labels:
+        - "dependency"
+
+    # (deprecated) Features or APIs that are being phased out, but still functional.
+    - title: "⚠️ Deprecations"
+      labels:
+        - "deprecated"
+
+    # (bugfix) Placed near the top so that bug fixes always take priority
+    # over general scientific updates or refactoring.
+    - title: "🐛 Bug Fixes"
+      labels:
+        - "bugfix"
+
+    # (feature) Standard customer-facing features and structural additions.
+    - title: "✨ New Features"
+      labels:
+        - "feature"
+
+    # (science) Domain-specific mathematical changes or model updates.
+    # (technical) Deep algorithmic optimisations or background logic shifts.
+    - title: "🔬 Scientific & Algorithmic Updates"
+      labels:
+        - "science"
+        - "technical"
+
+    # (documentation) Changes isolated to READMEs, inline code docstrings,
+    # scientific documentation, working practices, or
+    # other non-functional documentation updates.
+    - title: "📚 Documentation"
+      labels:
+        - "documentation"
+
+    # (optimisation) Direct speed execution metrics, runtime improvements,
+    #  Memory, storage, or other resource optimisations.
+    - title: "⚡ Performance Improvements"
+      labels:
+        - "optimisation"
+
+    # (refactor) Code cleanup, modularisation, or other internal improvements.
+    - title: "♻️ Refactoring"
+      labels:
+        - "refactor"
+
+    # (build) Changes affecting build tools or external compiler toolchains.
+    # (chore) General housekeeping, license updates, or minor administrative tasks.
+    # (ci) Changes to GitHub Actions workflows, CI/CD pipelines, or other automation.
+    - title: "🛠️ Maintenance"
+      labels:
+        - "build"
+        - "chore"
+        - "ci"
+
+  # Global Exclusions: Any PR matching these labels will be completely hidden
+  # from the final changelog output, taking ultimate precedence over categories above.
+  exclude:
+    labels:
+      - "ignore-changelog"  # Escape-hatch label to manually suppress a specific PR from the logs.
+      - "test" # Changes related to testing frameworks or test cases.
+      - "wip" # Work in progress PRs that are not ready for release.
diff --git a/pyproject.toml b/pyproject.toml
index e5ec9b4..1e74d12 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,6 +18,12 @@ respect-gitignore = true
 exclude = [
     ".github/pull_request_template.md",
 ]
+disable = [
+    "MD033",  # Inline HTML
+    "MD034",  # Bare URL used
+    "MD036",  # Emphasis used instead of a header
+    "MD041",  # First line in file should be a top level header
+]
 [tool.rumdl.MD013]
 line-length = 80        # Keeps normal paragraph text restricted to 80 chars
 code-blocks = false     # Disables the 80 char limit strictly for fenced code blocks