Concern about water quality has become an important environmental issue in the world, the United States, and Virginia. Volunteers have increasingly stepped forward to assist in the water quality monitoring task, and both state and federal protection agencies increasingly depend upon such voluntary assistance. The Izaak Walton League's Save Our Streams (SOS) is one such volunteer citizen water quality monitoring program. Recruiting, training, organizing and retaining volunteers are among the most resource intensive tasks of volunteer organizations. The purpose of this thesis is to document the motivations of SOS volunteers and the primary causes of their attrition in order to improve the SOS program as well as to enhance the experience of SOS volunteers. We also compared motivations of SOS volunteers, differences in SOS volunteers' evaluation of the program, and suggestions for improvements by varying participation levels in volunteerism. We found that SOS volunteers are primarily motivated by a desire to protect streams and to improve water quality. Learning about streams and teaching these concepts to others were also important motivations. Volunteers cited not enough time and having too many other obligations as the main reasons why they stopped participating in SOS activities. Recruitment and retention of SOS volunteers may be aided by providing feedback about how volunteer data are being used by protection agencies to protect streams, and providing opportunities for learning about streams and teaching these concepts to others. Lastly, we found that those volunteers who were most active in SOS differed in their motivations for participating, tended to be the most critical of the services and materials, and were most adamant about their data being used to protect streams. / Master of Science