Audit strategy is the overall plan of the audit which sets the direction, scope, and timing of the whole audit process. Audit strategy is set at the beginning of the audit and is a vital part of the audit planning process.
Audit strategy generally means the combination of audit approach to be used, resources management and allocation, timing of the audit and the way how the audit engagement is managed. For example, the auditor will use risks based audit approach or top-down approach to conduct audit assignment.
The audit strategy sets the scope, timing and direction of the audit. It also provides guidance for development of audit plan.
The audit plan on other hand, is more detailed than the audit strategy and it includes the nature, timing and extent of audit procedures to be performed by the engagement team members. The planning of these audit procedures takes place over the course of the audit as audit plan for engagement develops.