This article reports on a research study designed to identify who participates in library-based summer reading clubs (SRCs) and why they elect to do so. To address this aim, questionnaires were completed by caregivers of 246 children upon enrollment to the SRC of a metropolitan library as well as 480 youth; the questionnaire was designed to learn more about enrollees with respect to basic demographics, home environment, and motivational attributes. Results of this study suggested that those who enroll in SRCs are relatively diverse with respect to race/ethnicity and socioeconomic status; however, enrollees also tend to be motivated toward reading and to be capable readers. Implications for broadening community members' participation in SRCs are discussed.