Microbial alpha-amylase being a vital enzyme in industrial biotechnology, has also received enormous attention in academic field. Although a huge number of alpha-amylases from different sources have been mentioned in the literature, only few of them are able to meet the industrial demands. Thermostability, pH tolerance, calcium independency and oxidant stability and very high starch hydrolyzing efficiency are the important criteria for the diverse applications of alpha-amylase in starch based industries. Owing to biotechnological importance, its stability is a major concern for its economic viability. Stable microbial alpha-amylase can be obtained: (i) from extremophiles and genetically manipulated non extremopliles, and (ii) through improving stability by immobilization, chemical modification, protein engineering and augmenting with different additives. The present review is an attempt to compile the different strategies employed till date to obtain stable alpha-amylase. (C) 2016 Published by Elsevier Ltd.