A critical review of national and international theoretical as well as empirical work on psychological contract is presented. We have developed the issues around the following topics: nature and definition of the construct; processes of construction and development of psychological contracts; evaluation of breach and violation; methodological and measurement matters. The analysis emphasizes some important theoretical and methodological issues that are still under debate: discriminant validity of the three types of psychological contract; consistency between definition and operationalization of contract, breach and violation; measures of fulfillment. In the conclusions, guidelines for future research are suggested, emphasizing the necessity to conduct longitudinal studies that consider both contractual agents.