A methodological application of mass customization principles in engineer-to-order (ETO) processes is expected to lead to shorter lead times, increased quality as well as cost reductions. Product and process configurators, commonly used in mass customization processes, have to be adjusted according to ETO product and process requirements for their successful application in an ETO environment. In this paper the organizational requirements for a successful adaption of configurators to ETO processes are identified and structured. A Business Process Matrix capable of categorizing the implications of using product and process configurators in an ETO environment is developed.