To improve collaboration with audit clients during an engagement, it is effective for internal auditors to discuss the engagement plan with the client so they understand the reasoning behind the approach (2), and to review test criteria and procedures where the client expresses concerns about the type of tests to be conducted (3). This approach fosters transparency, helps manage client expectations, and builds trust. Obtaining control concerns before the audit (1) is also useful but less directly related to collaboration during the engagement. Providing all observations at the end of the audit (4) might not facilitate ongoing collaboration during the audit process. References: IIA Standard 2200 – Engagement Planning, IIA Standard 2400 – Communicating Results