This book is on the application of fuzzy set and rough set. Some examples of practical field are taken as HIV/AIDs, Crime against women in the North East Region of ndia etc and the utility of fuzzy and rough set in this cases are shown in this book. The book is very helpfull for the upcoming Researchers as they may take the idea of how to develop a new model and apply it in practical field. Also it may help the social Scientist for justifying there results by the help of this model.