California's minimum nurse-to-patient staffing ratio law, the nation's first, was implemented in 2004. This study had two aims: (a) to evaluate the effect of the nurse-to-patient ratios law on nurse job satisfaction in order to advance the debate over the merits of nurse staffing law, and (b) to compare California nurses who were satisfied against those who were not, in order to facilitate the development targeted retention interventions based on empirical evidence. The sample's overall job satisfaction increased significantly as the years passed, suggesting the nurse-to-patient ratios law was associated with improvements in nurse satisfaction. Satisfied RNs were more likely to have a balanced and financially secure life that included a partner, children living at home, higher hourly wages, and higher income from sources other than a nursing job. Nurses working in direct patient care positions remained dissatisfied in larger proportions than those working in other types of positions, even after the nurse-to-patient ratios were implemented. More nurses are satisfied today than before the ratios; nevertheless, far too many nurses (18.5%) have job satisfaction scores that are neutral or worse.