As grain legumes continue to be used for various food and health forms, after suitable processing and manufacturing of legume-based products, aspects such as growth, yields, physiological stress and genetic manipulation remain significant topics for the enhancement of their utilisation, to explore new potential and diversify their genetic resources. Future research focusing on the physiological response and genetic improvements of legumes need to be prioritised to improve the utilisation and nutritional quality. The purpose of this chapter is to serve as an introduction to advances made in grain legumes, that are presented in various chapters of this book. The discussion is generalised and intended to provide a comprehensive view on the effect of stress on legume growth and yields. Included in this chapter are (a) a brief discussion on legume origin and classification, (b) brief survey on legume growth, yield and the impact of stress (biotic or abiotic stress) and (c) overview on breeding strategies available for genetic improvement of grain legume species, both conventional and non-conventional technologies.