Abstract: New academic programs in environmental prompted a citation analysis of faculty by the Texas Tech University Library (TTU). The purpose of this study is to characterize the citation patterns of the interdisciplinary field of environmental and human health as compared with other disciplines and to apply the results to collection development. Twenty-four articles were selected from 1996 and 1997 with over 1600 citations to more than 950 listed references. The average age of citations was 10.5 years for journals and 9.4 years for books. On average, journals were cited 67% of the time while books were cited 17% of the time. Proceedings, theses, and technical reports were also cited but that data was not applied to collection development. The impact on collection development has been to identify a small number of specific books which were frequently cited but were not in the collection and to identify important subject terms with which to guide the selection of related books. Finally, 12 new subscriptions to frequently cited journals will be reviewed with faculty to determine their suitability as additions to the collection. This paper was also published in the March 1999 issue of the electronic journal LIBRES. (http://www.curtin.edu.au/curtin/dept/sils/libres/libre9n1/toxcite.htm) INTRODUCTION In response to two distinct requests from life faculty on the TTU campus for a description of library support for new environmental studies programs, a document was prepared describing the collection, document delivery service options, spending patterns for acquisitions, etc. [Appendix E] In order to better understand how to support the research activity of these faculty, especially the group at the new Institute of Environmental and Human Health (TIEHH), a citation analysis was undertaken which would allow for refining the original description of program support by the University Library. It was also hoped that such a study would add a qualitative dimension to the Library's effort to gather use data amidst an ongoing debate over the validity of journal reshelving counts. TIEHH was formed as a joint venture between Texas Tech University and Texas Tech University Health Sciences Center in 1997. It is dedicated to be a leader in research and teaching between environmental and human health. It will implement science and technology in the interface of good environmental policy and economic development. The charter faculty of the Institute [Appendix A] established a solid record of original research and service while at Clemson. A representative sample of their scholarly output in 1996 & 1997 constitute the study sample for this analysis. LITERATURE REVIEW Citation studies reveal much about scholarly communication and can be an effective tool to guide collection development in academic libraries. These studies typically take one of two directions: local or global. Studies of local faculty are believed by many to yield more relevant results than global investigations to assist librarians making serials selection decisions for their institutions. Aside from practical applications, citation studies offer objective insight into the fundamental research behavior of faculty and graduate students. For example, citation studies have been used to better understand how invisible colleges communicate, to identify discipline specific core journals, to make distinctions in research patterns between pure and applied scientists, etc. In a study comparing two plant journals considered either applied or basic in scientific content, Nordstrom (1987) characterized each based on citation age, proportion of cited formats, number of citations per article, and the distribution of citations among sections of each publication. He reported that basic publications generally cited more works and that these works tended to be somewhat older than the applied counterpart. …