Statement on Auditing Standards (SAS) No. 70, Service Organizations, is a widely recognized auditing standard developed by the American Institute of Certified Public Accountants (AICPA). A service auditor's examination performed in accordance with SAS No. 70 ("SAS 70 Audit") is widely recognized, because it represents that a service organization has been through an in-depth audit of their control objectives and control activities, which often include controls over information technology and related processes. In today's global economy, service organizations or service providers must demonstrate that they have adequate controls and safeguards when they host or process data belonging to their customers. In addition, the requirements of Section 404 of the Sarbanes-Oxley Act of 2002 make SAS 70 audit reports even more important to the process of reporting on the effectiveness of internal control over financial reporting.
One of the most effective ways a service organization can communicate information about its controls is through a Service Auditor's Report. There are two types of Service Auditor's Reports: Type I and Type II.
A Type I report describes the service organization's description of controls at a specific point in time (e.g. June 30, 2003). A Type II report not only includes the service organization's description of controls, but also includes detailed testing of the service organization's controls over a minimum six month period (e.g. January 1, 2003 to June 30, 2003).
About SAS 70 
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