Originally developed to provide background information for participants in a 1992 external review of maize international testing at CIMMYT, this publication describes CIMMYT's clients, international and regional testing of maize germplasm by the Center and national program cooperators, and the role of such testing in germplasm improvement and distribution. Appended material summarizes major conclusions and recommendations of recent internal reviews of maize international testing at CIMMYT and provides an overview of the Center's Maize Program.iv, 108 pages