This research undertakes a contingency theory examination of strategy and cost system alignment based on customer retention and customer profitability analysis. Previous research and consultancy advice has promoted the benefits of a firm following a customer retention strategy. They claim that in order to support the strategy a firm should have a customer profitability analysis system in place. Yet often what is prescribed as good practice is not observed in firms. This inconsistency is explained using contingency theory. Initial qualitative evidence was collected from four industry sites to determine whether the above strategy-cost system alignment was present. An analysis of these findings suggested that the customer retention-customer profitability analysis system relationship was contingent on a range of factors. As a result, a contingent theory of this relationship was developed from the four sites, and this theory was then tested in a survey of 862 people from 431 firms. The survey results provide support for the propositions developed from the qualitative evidence. It is likely that firms will follow multiple operational marketing strategies and have cost management systems in place to support those strategies. Although customer retention is a very important operational marketing strategy, a significant number of firms do not have customer profitability analysis systems in place to support the strategy. Many contingent factors were identified. Customer profitability analysis implementation is dependent on industry type; size; the difficulties involved in determining customer costs; whether the organisation has a champion for the system; the relationship between the marketing and accounting functions in a firm; and the available labour resources to facilitate implementation. Further, it is apparent that customer profitability analysis information is not essential to support a customer retention strategy. Customer revenue information can be substituted and the firms are satisfied with the level of management accounting system support for their operational marketing strategies. However, many respondents see the value of customer revenue, customer cost and customer profitability information, providing opportunities for future design of such systems as well as research into their development.