Audit Technique Guides: May 2008 - Research Credit Claims Audit Techniques Guide (RCCATG): Credit for Increasing Research Activities § 41* June 2005 - Revised Research Credit Audit Technique Guide January 2005 - Research Credit Audit Techniques Guide for Aerospace Industry April 2004 - Research Credit Audit Techniques Guide for Phamaceutical Industry Directives: August 2005 - Section 280C April 2004 - Planning and Examination of Research Credit in a Branded Pharmaceutical Company March 2002 - Field Directive on the Use of Statistical and Judgement Sampling in Research Field Cases PDF Field Directive - Use of Sampling Methodologies in Research Credit Cases PDF Guidelines: Audit Guidelines on the Application of the Process of Experimentation Requirement for all Software