Data in this report reflect responses from 86 four-year private institutions that collectively enroll approximately 261,189 undergraduate students (according to data reported to the Integrated Postsecondary Education Data System (IPEDS)). Respondents participated in the Ruffalo Noel Levitz (RNL) national electronic poll of "Effective Practices for Student Success, Retention, and Completion" between January 17 and March 4, 2023. The poll was emailed to student affairs, academic affairs, and retention officers at accredited, degree-granting institutions across the United States. To report the findings as accurately as possible, the rankings of effectiveness were based only on the relative effectiveness options that were given to respondents: "very effective," "somewhat effective," and "minimally effective," rather than including the fourth response, "practice not used." RNL polled campus retention leaders to answer the following questions: (1) Which student retention practices do private colleges and universities use the most? (2) Which are the most effective? and (3) Where are the best opportunities to improve student retention and completion? This report can be used to perform an informal audit of current practices, noting practices that are in place, and highlighting those that can be considered in retention efforts.