Shape your heart to front the hour, but dream not that the hour will lost. Alfred Tennyson Locksley Hall Sixty YeO!, After Numerous advances in the life sciences have necessitated the need to develop gentle, quick and economical methods for separation of proteins/enzymes. Affmity-based separations, with their high selectivity, have thus come to be used more frequently. In the beginning, we just had atrmity chromatography. Today we have several strategies that employ atrmity interactions for separa- tion and analysis. This book is an attempt to provide a short introduction and illustrative protocols for some important and current affinity-based approaches inthe area ofdownstream processingofenzymes/proteins. Today, people from a variety of disciplines have to purify proteins. It is hoped that this book will provide some quick insight into the various available options and guide even a novice (in the area ofprotein separation) to obtain his/her target protein at the level of purity that he/she desires.