This paper reports the results of a mapping program in the vicinity of the Boston gold deposit near Hope Bay, south-west Nunavut. It first reviews the regional geology, the granitoid rocks of the Hope Bay volcanic belt, and their contact relationships with the belt. It then focusses on the geology of the deposit area, with descriptions of the rock types, the geologic structures, and the gold mineralization. Finally, implications of the findings for mineralization in other areas of the Hope Bay belt are discussed.