Staffing is the dominant input in the production of nursing home services. Because of concerns about understaffing in many US nursing homes, a number of states have adopted minimum staffing standards. Focusing on policy changes in California and Ohio, this paper examined the effects of minimum nursing hours per resident day regulations on nursing home staffing levels and care quality. Panel data analyses of facility-level nursing inputs and quality revealed that minimum staffing standards increased total nursing hours per resident day by 5% on average. However, because the minimum staffing standards treated all direct care staff uniformly and ignored indirect care staff, the regulation had the unintended consequences of both lowering the direct care nursing skill mix (i.e., fewer professional nurses relative to nurse aides) and reducing the absolute level of indirect care staff. Overall, the staffing regulations led to a reduction in severe deficiency citations and improvement in certain health conditions that required intensive nursing care. Copyright © 2014 John Wiley & Sons, Ltd.