User impersonation is a critical feature for troubleshooting and support within applications, allowing admins or support teams to take on a user's identity to diagnose issues without needing their credentials. This feature enhances user experience testing, training, onboarding, data access, recovery, auditing, and compliance. However, it poses security and privacy risks if not implemented carefully, requiring stringent controls, logging, and clear policies. Implementing user impersonation involves ensuring strong permissions, secure authentication, and a clear UI indication that impersonation is active. While developing this feature in-house can be complex, platforms like Clerk offer built-in user impersonation capabilities, simplifying the integration process and mitigating potential security issues.