Parenting programs have the potential to improve the health and well-being of parents and children. A challenge for providers is to recruit and retain parents in programs. Studies researching engagement with programs have largely focused on providers', policy makers', or researchers' reflections of their experience of parents' participation. We conducted a systematic review of qualitative studies where parents had been asked why they did or did not choose to commence, or complete programs, and compared these perceptions with those of researchers and those delivering programs. We used data-mining techniques to identify relevant studies and summarized findings using framework synthesis methods. Six facilitator and five barrier themes were identified as important influences on participation, with a total of 33 subthemes. Participants focused on the opportunity to learn new skills, working with trusted people, in a setting that was convenient in time and place. Researchers and deliverers focused on tailoring the program to individuals and on the training of staff. Participants and researchers/deliverers therefore differ in their opinions of the most important features of programs that act as facilitators and barriers to engagement and retention. Program developers need to seek the views of both participants and deliverers when evaluating programs.