The entire Droplet Model approach was conceived and carried out in collaboration with W. J. Swiatecki, whose influence is to be seen in every part of the work. The theory described here and the table of nuclear properties that appears at the end are the culmination of a series of developments that we have undertaken together off and on over the last twelve years. During that time the Droplet Model has found applica­ tion to a broad range of static (and more recently dynamic) macroscopic nuclear properties. The text begins with a historical introduction that briefly traces the development of the Droplet Model and references are given to the earlier work. After that the Droplet Model itself is presented and the values of the coefficients are given. In the following section descriptions are given, of the other terms which must be added to obtain a complete expression for the prediction of atomic mass defects. These sections are all quite brief with the exception of the one in which the "Wigner term" is described. This section (contributed by W. J. Swiatecki) contains a somewhat fuller discussion of our form of the Wigner term than might be thought appropriate in view of the many standard expositions of Wigner's supermultiplet theory and his "Uniform Model" of nuclear masses.

I. Introduction.- II. The Droplet Model.- III. Mass Formula.- A. Shell Corrections.- B. The Even-Odd Term.- C. The "Wigner" Term.- IV. Comparison with Experiment.- A. Beta-Stability Properties.- B. Final Mass Differences.- C. Fission Barriers.- D. Deformations.- E. Radii.- V. Remarks.- References.- Table of Masses, Deformations, Fission Barriers, Radii, etc..