Supersymmetry, supergravity and superstring are the most popular research topics in particle physics. In particular, the phenomenological studies beyond the standard model have become very popular in view of possible identification or exclusion of supersymmetric particles in the future. Also, the lightest supersymmetric particle in most supersymmetric models can be a good candidate for dark matter in the universe.The recent developments in supersymmetry with important applications to particle physics are the main theme of this book, which includes superstring calculations with D-branes, TeV-scale gravity, superstring- and supergravity-inspired interactions, supersymmetric GUT, supergravity phenomenology, and cosmological implications of LSP.