As businesses increasingly use electronic data processing (EDP) techniques to process their accounting systems, auditors must gather critical information more efficiently. Such tools and techniques as electronic data interchange, the Internet and other modern technological subjects signal the end of the traditional audit. Technology has made inputting information for transactions and events more simple ‐ and evaluating the related controls and results more critical. Accumulating sufficient evidence needed to construct an informed decision means understanding where to look for that evidence, what control procedures to consider and how to evaluate those procedures. The purpose of this article is to draw attention to these issues and the recently issued SAS No. 80, which offers auditors guidance to accumulate sufficient evidence to audit their computerized clients. We also address some issues auditors may face in evaluating the security control in their clients’ businesses.