Genetic variability is a measure of the tendency of individual genotypes in a population to vary from one another. Exploiting the existing and/ or creating new variability is a technique of any crop improvement program. Not all breeding works start with selection from existing population or crossing. For crops like soybean adaptation of genotypes to areas where it has not yet been produced is essential step which depends on germplasm introductions. Under Ethiopian condition soybean has not yet been well domesticated because of different factors. However, there is a potential for future because of the upcoming demand for soybean seed by emerging factories. This review and research highlight can help the efforts have been done both in research and development strategies in countries like Ethiopia. Therefore, this book is helpful for researchers, students and extension workers during selecting varieties for different environments. It will also help determine the environments suitable for the trait of interest under selection.