Interpretive programs are offered by parks and public lands to inspire the visitors to further appreciate the heritage resources presented and protected within parks. These programs and services add an additional dimension to park visits, may increase enjoyment, provide visitors with a richer understanding of heritage resources, create opportunities to influence visitor behaviors in ways helpful to managers, and possibly provide motivations for visitors to extend their stay. Any potential desired outcome resulting from the strategic use of interpretative programs requires participants, and the broader the audience, the wider the influence. Consequently, a study of the variety of reasons that people are attentive or not to interpretive services could provide ways to modify programming in terms of publicizing, delivery, and content. Specifically, this study explored the types of constraints to attending interpretive (or ranger-led) programs to that visitors experience. Visitors who attended interpretive programming and those who do not were asked to describe their perceptions about the value of interpretive programming, the types of people who attend interpretive programming, how content is presented, and the topics of the programs. Qualitative interviews and demographic surveys were conducted with 57 campers at three different developed campgrounds at state parks in the southern Appalachian Mountains. Using a pragmatic approach, the themes that developed included the role of unstructured time, information availability, lifestages, environmental issues programming, and competing activities. Through increased awareness of constraints to participation, interpreters should be able to troubleshoot existing programs, schedule programs at optimal times and locations, and publicize programs more effectively. Through this process, interpreters could increase their ability to meet park management objectives.