The mechanical and physical properties of molybdenum and molybdenum-base alloys have been rather extensively documented in the past decade. Almost all of these data have been developed in connection with investigations of wrought bar stock; very little data have been accumulated on the properties of sheet. On the other hand, considerable interest has developed in recent years in the utilization of molybdenum and molybdenum-base alloys in the form of sheet products. This interest is concentrated on sheet of about 1/16-in. gage. This paper represents a summary of the several investigations that were initiated to determine some of the mechanical properties of unalloyed molybdenum and of three molybdenum-base alloys, processed to 1/16 in. thick sheet from vacuum arc-cast ingots.