This investigation proceeded along two lines. First, individuals gathered data on 208 HCPs that had been approved by August 1997 in order to obtain basic descriptive information about plans. Second, the group conducted a more comprehensive analysis for a focal subset (43) of these plans. The HCPs in the focal subset range widely in geographic location, size, duration, methods, and approval dates. For this in-depth investigation, we developed two separate data questionnaires: one asked for information on theplans themselves, and the other focused on listed species and their treatment within HCPs. These questionnaires included information about what scientific data were available for use in formulating the HCP, how existing data were used, and the rigor of analysis used in each stage of the HCP process. As a whole, the questions were designed to generate a detailed profile of each HCP and to document the use (or lack thereof) of scientific data and tools. Plans were not judged overall; rather, questionnaires focused on different stages of the planning process, including the HCPs assessment of (1) the status of the species; (2) the take of species under the HCP; (3) the impact of the take on the species; (4) the mitigation for the anticipated take; and (5) the biological monitoring associated with the HCP. All of the data sheets, plan descriptions, and other detailed results from this effort are available on the NCEAS website: https://admindb.nceas.ucsb.edu/admin/db/web.ppage?projid_in=2049 . All descriptions of the data set contents are provided through the HCP report available at the web site above. In general the data sets contain responses to the questionaires from the HCP surveys. Each question is listed by question number in the data set and is described in detail in the HCP report (see web site). In addition, a listing of thecontents of the four final data sets is provided in the file hcp-load.lst.