The Internal Auditing profession evolved steadily with the progress of management science after World War II. It is conceptually similar in many ways to financial auditing by public accounting firms, quality assurance and banking compliance activities. While some of the audit technique underlying internal auditing is derived from management consulting and public accounting professions, the theory of internal auditing was conceived primarily by Lawrence Sawyer (1911-2002), often referred to as "the father of modern internal auditing";[3] and the current philosophy, theory and practice of modern internal auditing as defined by the International Professional Practices Framework (IPPF) of the Institute of Internal Auditors owes much to Sawyer's vision.