diff --git a/templates/run_details.html b/templates/run_details.html
index 9f2c435..ed0bd72 100644
--- a/templates/run_details.html
+++ b/templates/run_details.html
@@ -16,7 +16,15 @@
         <button class="btn btn-primary me-2" data-bs-toggle="modal" data-bs-target="#modifyRunModal" data-bs-toggle="tooltip" title="Create a new run based on this one, but with different instructions (e.g. 'Make it darker').">
             <i class="fas fa-pen-fancy me-2"></i>Modify & Re-run
         </button>
-        <a href="{{ url_for('project.view_project', id=run.project_id) }}" class="btn btn-outline-secondary">Back to Project</a>
+        {% if run.status not in ['running', 'queued'] %}
+        <form action="{{ url_for('run.delete_run', id=run.id) }}" method="POST" class="d-inline ms-2"
+              onsubmit="return confirm('Delete Run #{{ run.id }} and all its files? This cannot be undone.');">
+            <button type="submit" class="btn btn-outline-danger">
+                <i class="fas fa-trash me-2"></i>Delete Run
+            </button>
+        </form>
+        {% endif %}
+        <a href="{{ url_for('project.view_project', id=run.project_id) }}" class="btn btn-outline-secondary ms-2">Back to Project</a>
     </div>
 </div>
 
diff --git a/web/routes/run.py b/web/routes/run.py
index 117b2e9..51d5357 100644
--- a/web/routes/run.py
+++ b/web/routes/run.py
@@ -1,5 +1,6 @@
 import os
 import json
+import shutil
 import markdown
 from datetime import datetime
 from flask import Blueprint, render_template, request, redirect, url_for, flash, session, send_from_directory
@@ -393,6 +394,30 @@ def revise_book(run_id, book_folder):
     return redirect(url_for('run.view_run', id=new_run.id))
 
 
+@run_bp.route('/run/<int:id>/delete', methods=['POST'])
+@login_required
+def delete_run(id):
+    run = db.session.get(Run, id)
+    if not run: return "Run not found", 404
+    if run.project.user_id != current_user.id: return "Unauthorized", 403
+
+    if run.status in ['running', 'queued']:
+        flash("Cannot delete an active run. Stop it first.")
+        return redirect(url_for('run.view_run', id=id))
+
+    project_id = run.project_id
+
+    run_dir = os.path.join(run.project.folder_path, "runs", f"run_{run.id}")
+    if os.path.exists(run_dir):
+        shutil.rmtree(run_dir)
+
+    db.session.delete(run)
+    db.session.commit()
+
+    flash(f"Run #{id} deleted successfully.")
+    return redirect(url_for('project.view_project', id=project_id))
+
+
 @run_bp.route('/run/<int:id>/download_bible')
 @login_required
 def download_bible(id):