A survey was done over a 2^/^ year period on the Orange-throated Whiptail, Cnemidophorus hyperythrus beldingi, throughout its range in Southern CaUfomia. The species has been presumed to be threatened by loss of habitat due to human activity. The study included determining the lizard's past and present distribution from museum and California Department of Fish and Game records, the literature, questionnaires, correspondence, and field surveys. Field surveys also were used to evaluate lizard habitat requirements and abundance. Detailed studies at the population level and laboratory and field studies on habitat requirements and behavior rounded out the study.