This chapter summarizes the key metrics and references for evaluating personalized marketing systems. The chapter advocates starting with a conceptual framework that relates various aspects of the system to business goals, with key mediators in between. The chapter organizes metrics into groups that measure predictive accuracy (RMSE, MAE), classification accuracy (precision, recall, F1), ranking (nDCG, MRR), and features describing the recommendation (diversity, novelty, serendipity, coverage). Subjective user evaluations such as perceived privacy and satisfaction are identified.