Lipases (triacylglycerol acylhydrolase; EC 3.1.1.3) catalyze the hydrolysis of triglycerides to free fatty acids and glycerol. Lipases are ubiquitous in nature, but only microbial lipases are commercially significant. The primary goal of this work was to study the microflora of oil mill waste, to screen a hyper lipase producing bacterial strain and to study the effect of production and reaction conditions on enzyme activity from traditional oil mill soil of Himachal Pradesh (India). This book will help students who are interested to pursue their research in enzyme technology and industrial microbiology/biotechnology. The efforts have been made to compile available information of the subject and to provide simple, authentic and recent account of each and every topic. I am very grateful to my teacher Ms. Sumita Thakur who helped me in writing this book. I am thankful to publisher for their cooperation and keen interest in publication of my work. I owe my special thanks to my parents Ms. Sandhya Verma and Mr. H.R. Verma and my brother Mr. Maneesh Verma who have always inspired me. Constructive and healthy suggestions will be most welcomed. Neelam Verma