This book is trying to describe consumer behavior in terms of how roles in decision-making process are divided among members of households. Results are compared with stereotypes in decision-making process. Because of absence of any similar research, this book is focusing on formulating approach to this problematic. The main objective of the book is to identify and find the way how to describe process of decision making among members of household. Thus, which roles are taken by household s members towards to process of purchasing of specified consumption basket, including general products consumed by households, which were carefully chosen. It would be described how decisions among family member differ according to product categories and type of households. In other words how an involvement of each member of a household differs depending on product s category and it close environment. We will emphasize comparison of results with stereotypes in consumer behavior process. It is worth of mentioning that the secondary objective is to identify an approach to this problematic in general, in terms of processing, formulating of the objectives and their methods of fulfilling them.