Surface coverage is a major control parameter for shot peening and has substantial influence on the reliability and uniformity of the process. It restrains quality variations that may cause premature failure or malfunctioning of the treated part. Despite the role of surface coverage in process quality, a general description and a unique standard method for its practical control and prediction are not yet established. This paper provides a general review of the definitions and requirements of surface coverage, its practical, theoretical and computational evaluation approaches. In the end a statistical study is performed on a coverage estimation method already developed by the authors. The results of the statistical study result in development of a complementary technique for coverage assessment which ensures full coverage with an optimum number of impacts. Different models are explained and critically discussed. (C) 2012 Elsevier B. V. All rights reserved.