The American Institute of Certified Public Accountants (AICPA) and the Institute of Internal Auditors (IIA) have positioned the auditing professions to become assurance professions. What is the difference between assurance services, attestation services, and auditing services? What are the economic issues that drive the increased demand for assurance services? What is one assurance engagement and one attestation engagement other than an audit of financial statements? What are the differences between the two?