) Background and Significance: There is an urgent need for a high quality prostate cancer tissue resource that is available to the entire research community and is large and reliable enough to allow significant outcomes and validation studies. It also needs to offer material that meets the technical demands of researchers of the next decade, such as high quality DNA, mRNA and proteins. Approach: The proposed tissue resource at the Medical College of Wisconsin will respond to these needs by accruing 2,000 cases of archival and 800 fresh prospective prostatectomies with prostate cancer. It will also accrue 1,000 needle biopsies and appropriate control tissues. Each case will come with a database showing a complete set of pathological parameters (35 query elements), clinical data and outcomes information (22 query elements). Representative electronic digitized microphotographic images will be attached for each case. Another goal is to meet the demand for high throughput screening of prospective biomarkers with tissue microarrays. The use of tissue microarray slides that contain hundreds of minute tissue samples, one from each patient, promises a rapid and resource conserving approach to marker analysis. This screening tool saves not only tissues, but also labor and materials by the investigator requesting the samples. Researchers will also need to have easy access to histological materials that will separate stromal from epithelial components of cancer, or that will separate prostatic intraepithelial neoplasia from adjacent tumor. The most reliable way of doing this today is by laser capture microdissection (LCM). The establishment of LCM services at MCW would provide established researchers with access to purified cells for the isolation of specific subsets of DNA, RNA, and protein. Ideal environment for a tissue resource: The Medical College of Wisconsin is uniquely poised to offer a high quality resource: Approximately 60,000 surgical pathology cases per year, including almost 250 prostatectomy cases per year, are all under one established administrative unit. A Cancer Registry service tracks all the clinical information in a centralized location and also responds to a single established administrative unit; each individual case will be reviewed by a select group of pathologists for Gleason grading and other defined parameters; the clinical records of each case will also be reviewed to obtain at least 22 clinical and outcome datapoints. The proposed group of investigators have previous experience in tissue banking, LCM, and prostate cancer research. Experienced state-of-the-art informatics support is also available.