A proposed specification covering handling characteristics and physical and chemical properties of bone cement composed primarily of methyl methacrylate has been prepared on the basis of data from the authors' studies and from various other sources. Under handling characteristics, requirements included relate to dough, handling and setting time, proper plasticity for insertion and temperature rise on setting. Mechanical properties specified include compressive strength and indentation and recovery characteristics. Maximum limits are proposed for water sorption and solubility. Suggested packaging requirements are also included.