There is a confusion between the terms audit and assessment. Actually I was confused by these two words until not so long ago, so I figured it might help to shed some light on this ambiguity.

An audit is a process to verify the conformance of an entity to a given standard. It consists in gathering evidence of conformance or nonconformance. Therefore, it results in a success or a failure with regard to the scope of the audit. Verification and inspection are synonyms of audit.

Example of audit: Verify that the project management practices comply with a set of best practices defined by an instance of the Project Management Body of Knowledge (PMBOK).

An assessment, on the other hand, evaluates the efficiency and/or effectiveness of an entity and results in a measure of its performance with regard to the scope of the assessment. The goal of the assessment is to gain understanding in order to formulate a recommendation to improve the entity's situation. Appraisal and evaluation are synonyms of assessment.

Example of assessment: Evaluate the CMMI level of an entity.

Note that both audit and assessment can use the same base material, such as a given project management methodology, but their goal and the way they use the reference material will differ.

We can also distinguish audits from assessments by looking at:

• Attribution: An audit might explicitly point at specific people or groups of people as the cause for noncompliance (attribution). An assessment does not evaluate individuals (non-attribution). Of course, the result of an assessment might still be used to infer responsibility for failure or low scores.
• Fault: Whereas an audit results in a success or a failure (fault), an assessment usually provides a score that does not express success or failure (no-fault). With an assessment, one can freely decide which score constitutes a success or a failure if they want to, but this is done to identify the areas that should be improved and not to judge people.

As you can see, the difference doesn't lie only in the goal and in the process, but also in the mindset.

Additionally, we have to mention that the two words audit and assessment generate very different reactions. Audit is associated with distrust and punishment whereas assessment is often seen as an opportunity for improvement. Unfortunately I have personally witnessed audits disguised as assessments. Instead of resulting in a healthy improvement plan the results have been used to blame people and terminate projects.