This Book explains various measures of Intuitionistic Fuzzy Theory for the purpose of better decision making. It acquaints the readers not only with the mathematical aspect of generalized fuzzy theory but also explain various models by taking a hypothetical case study. Moreover, it provides deeper insight of the concepts like generalized fuzzy theory in medical diagnosis of diseases. In this era, the interdisciplinary approach towards the concepts is increasing and integrated so as to boost research. Therefore, the present efforts are to bring out the work can be useful to disciplines of decision sciences.