The implementation and development of market orientation in U.S. hospitals was examined to identify a set of internal and external market intelligence behaviors to ensure value to customers and long-term profitability for hospitals. This quantitative study empirically tested a 4-phase grounded theory model in a hospital setting, and a scale by which implementation can be assessed and monitored was developed through a cross-sectional survey. The survey was sent by email to a target population of 18,934 hospital executives at acute care and critical access hospitals throughout the United States and its territories. Data were collected and analyzed through correlation and multivariate regression analysis and structural equation modeling. The findings suggest that market orientation does develop in accordance with the 4 main phases of market orientation development, and the progression occurs sequentially. There does appear to be a positive correlation related to the degree of progress through development stages, increasing market-orientation score and perceived performance; however, meaningful increases in the positive impact on market orientation and performance do not show until the last stage of development, and there is a clear chronology in the 4 stages. The study data supports that in the developmental process, cultural transformation benefits precede behavioral transformation benefits, interfunctional coordination is a moderating variable positively affecting performance results, and information generation partially mediates customer and competitor orientations. The study’s implications relate to future managerial application of a valid reliable scale to measure and assess market-orientation development phases in hospitals and other industries. Keywords: market orientation, healthcare, hospital, performance improvement, development phases, customer orientation IMPLEMENTATION OF MARKET ORIENTATION