Auditing & Assurance Standard 15 provides guidance on audit sampling for auditors. It establishes that auditors can use statistical or non-statistical sampling methods to evaluate a sample of items from a population to obtain sufficient audit evidence rather than examining all items. The standard provides guidance on designing an audit sample, including considering the audit objectives, population, stratification, sample size, tolerable error, and sampling risk. It also provides guidance on selecting the sample randomly, systematically, or haphazardly and evaluating the results.