: Several recent reports including the Institute of Medicine's """"""""Crossing the Quality Chasm"""""""" have called attention to systems or organizational level factors as critical to the improvement of health care quality in the United States. In addition, understanding the context or environment in which an organization exists is also important to crafting policy-relevant research. The predominance of managed care organizations over the last two decades is an example of an environmental influence that has changed the organization and delivery of health care in the United States. The purpose of the proposed research is to examine how the environmental context of an organization influences organizational structures and processes and ultimately affects the care delivered at the site. The clinical focus of this study is colorectal cancer (CRC) screening. To date, most of the research on the delivery of CRC screening has focused on individual patient-level factors, leaving the influence of organizational factors poorly understood. This cross sectional study uses data from several different sources including: Interstudy, the Area Resource File, and the Veteran's Health Administration (VHA). Ordinary least squares and multi-level logistic regression models will be used to explore: (1) the relationship between managed care penetration and adoption of managed care practices in the VHA that may affect CRC screening rates; (2) the relationship between managed care penetration and receipt of colorectal cancer screening within the VHA system; and (3) the effect of managed care penetration on the probability of receiving CRC screening inside the VHA system among those who received CRC screening. Understanding the relationship of organizational influences and variations in the delivery of CRC screening will provide a better understanding of the barriers to the use of this service. Such information may serve as the basis for the design of interventions to improve CRC screening. ? ?