Roles can be assigned to each business partner. The business partner must have been created in the corresponding role in order to carry out a a certain transaction with a business partner. The Role category describes the function of the business partner in a transaction and determines the rights and obligations of the business partner. You can call up various screens (views) in business partner maintenance based on the role category. The Role-View-Allocation takes place in business partner Customizing under Role-View-Determine allocation.