Provider knowledge is a potential barrier to adherence to clinical guidelines. The purpose of this study is to assess the impact of organizational, provider, and guideline factors on provider knowledge of a congestive heart failure (CHF) clinical practice guideline (CPG) in the Veterans Health Administration (VHA) health care system. We developed a survey to investigate institution-level factors influencing the effectiveness of guideline implementation, including characteristics of the guideline, providers, hospital culture and structure, and regional network. Survey participants were quality managers, primary care administrators, and other individuals involved in primary care CPG implementation at 143 VHA hospitals with ambulatory care clinics. Potential explanatory variables were grouped into 11 factors. Multivariate regression models assessed the association between these factors and reported levels of provider knowledge regarding the CHF guideline at the hospital level. Two hundred forty surveys from 126 of 143 (88%) VHA hospitals were returned. Provider knowledge of the CHF guideline was estimated as "great" or "very great" by 58% of respondents. Three predictor factors (dissemination approaches, use of technology in guideline implementation, and hospital culture) were independently associated (P < or = .05) with provider knowledge. Specific variables within these categories that were related to greater knowledge included physician belief that guidelines were applicable to their practice, distribution of guideline summaries, use of guideline storyboards in clinic areas, the use of technology (eg, electronic patient records) in CPG implementation, and establishment of implementation checkpoints and deadlines. Provider knowledge of guidelines is affected by factors at various organizational levels: dissemination approaches, use of technology, and hospital culture. Guideline implementation efforts that target multiple organizational levels may increase provider knowledge.