This volume presents the results of the medieval component of the Nemea Valley Archaeological Project (NVAP) survey conducted from 1985-1990. The archaeological evidence points to a proliferation of sites dating to the 12th–13th century A.D. There are two large sites and a substantial number of small sites on the lower slopes of the hills surrounding the Nemea Valley and in smaller valleys in the southern part of the survey area. Archaeological evidence of settlements from the late 13th-15th century is scarce, providing a contrast to the patterns documented for the 12th-late 13th century. This study is thus also concerned with general trends and important sociopolitical changes that affected such developments in the Nemea region in the medieval period.