The second edition of the International Standard ISO/DIS 2859-1(1997) is the revised version of ISO 2859-1(1989). Significant changes in this edition include the following; ⅰ) a new procedure for switching from normal to reduced inspection is used, ⅱ) optional fractional acceptance number sampling plans are added, and ⅲ) reduced plans are changed to eliminate the gap between the acceptance and rejection numbers. In this paper, major changes and additions incorporated into the revised version are discussed.