These volumes, a collection of a series of articles with commentary notes by the editor, describe supersymmetric theories for particle interactions from the earliest developments to the latest advancements. The book, divided into two volumes, will mainly focus its attention on subjects related to the application of N = 1 supersymmetry and supergravity to unified theories, encompassing all fundamental forces of nature. Particular emphasis is given to the ultraviolet cancellations in supersymmetric field theories, naturalness and hierarchy of scales, spontaneous symmetry breaking, super-Higgs effect and its applications to high energy physics. Both perturbative and non-perturbative aspects of supersymmetric field theories are covered. Over a hundred seminar papers are reprinted in these volumes.