The document discusses a study investigating the differential effects of customer relationship perceptions (CRPs) and relationship marketing instruments (RMIs) on customer retention and customer share development over time. The author develops a conceptual model examining how affective commitment, satisfaction, payment equity, loyalty programs, and direct mailings impact both customer retention and customer share development. The author hypothesizes that affective commitment and loyalty programs positively impact both outcomes, while direct mailings primarily influence customer share development. The study uses longitudinal data from a financial services company to test these hypotheses.