Due to deregulation within the area of telecommunications, an increasing number of Norwegian Telecom's former monopoly areas are, or will be, opened to free or licensed competition. This calls for a market and customer-oriented organization, with the clear strategy not to lose too many customers. In this context, customer loyalty is a major concern. In this study practical problems connected to the measurement of customer loyalty and related constructs are discussed, and some possible solutions are explored. Results from a survey conducted in January 1993 in the Norwegian telecommunication market, have been used as an empirical basis for decisions regarding measurement and research-design strategies. A research design for future tracking of customer loyalty, is presented.