This rule makes changes to the regulations governing the section 8(a) Business Development (8(a) BD) program, the U.S. Small Business Administration's (SBA or Agency) size regulations, and the regulations affecting Small Disadvantaged Businesses (SDBs). It is the first comprehensive revision to the 8(a) BD program in more than ten years. Some of the changes involve technical issues such as changing the term "SIC code" to "NAICS code" to reflect the national conversion to the North American Industry Classification System (NAICS).