Discuss the applicability of various auditing tests in a general framework of auditing procedures and auditing tests that have a more specific and defined range of 

applicability? For example, tests of controls are performed when the auditor is planning to rely upon internal controls thereby enabling the auditor to perform limited or moderate substantive testing. If internal controls are weak or non-existent, tests of controls may not be appropriate and substantive testing would be significantly increased. What factors may cause variation from client to client and industry to industry with respect to auditing.