AbstractA large number of tests based on observations made on compacts have been devised to evaluate the pressing and sintering characteristics of metal powders. These are summarized under four headings: behaviour during pressing, properties of the green compact, behaviour during sintering, and the properties of the sintered compact. The specifications which set down standard testing techniques are described and reviewed. The principles involved in the various proposed tests are given, together with any limitations or precautions that need special consideration. In a number of cases there is obvious scope for further study and research, and these are pointed out.