While numerous books have been published in the area of probiotics but no book has been reported exclusively on methods adopted in probiotics research. This book is aimed at researchers who are involved in conducting research on wide applications of probiotics. To establish any organism as probiotics, it needs to pass through number of tests. The isolation and identification techniques need to be chosen carefully. The assessment of probiotics attributes is to be done by a series of in-vitro and in-vivo experiments. Clinical trials are also conducted to evaluate the efficacy and safety. The use of latest genome based tools have enhanced the spectrum of understanding for probiotics.