Hospitals experiencing financial pressures are seeking to gain efficiencies through innovation. One solution is to engage hospitalists to help reduce the average length of stay (ALOS). This study considers whether and to what extent hospitalists affect ALOS and whether an association exists between the number of hospitalists per occupied bed (density) and ALOS. We examined 2,858 hospitals nationwide, including 20,180 hospital-years of data from 2007 through 2015 derived from the American Hospital Association Annual Survey database. Key findings showed that hospitals using hospitalists reported a statistically significant shorter ALOS than hospitals without hospitalists. The results also indicated a statistically significant decrease in ALOS for an increase in hospitalist full-time equivalent per occupied bed. This study is important because of the generalizability of its results and suggests that hospitals may form partnerships with hospitalists to improve hospital efficiency.