This document discusses challenges and best practices for CAPA (corrective and preventative action) programs. It outlines common pitfalls such as implementing actions that don't address the root cause, focusing on timelines over deliverables, and overusing "operator error" as a root cause. Best practices include using a multidisciplinary team approach, evaluating trends, and identifying all relevant inputs to the CAPA process. Effectiveness is best measured by metrics like recurrence rates and timeliness rather than just pass rates of proof of effectiveness. The document provides guidance on how to conduct a robust CAPA process.