Book Reviews of the microbalance technique. It starts out with an introduction by S. P. Wolsky and a review with many useful references by A. W. Czanderna. These chapters are followed by a most helpful and easily readable chapter on microbalance theory and design by R. L. Schwoebel. The last two chapters contain a discussion of micro-weighing with quartz crystal oscillators and a valuable review of vacuumcontrolled environment systems. Part II, written by a group of workers who have had wide experience in the use of microbalances, contains essential and up-to-date information concerning the uses and potential use of many types of microbalances. Not many years ago it was usually necessary for the investigator to assign and construct his own microbalance if it was to be used for a special purpose. This is no longer the case. Part III describes and in some cases critically discusses the merits of several commercially available instruments. Most people not interested in the microbalance per Be will find this part helpful. For a book written by so many authors, it is a well-coordinated effort and can be highly recommended as a timely and most informative volume on microbalances.