This study examines the effectiveness of nursing home regulation in the United States. We assessed whether the 50 states meet national guidelines for correcting nursing home problems in a timely manner and we identified state-level factors that may predict faster deficiency resolution. Nursing home deficiency citation data over a 5-year period (2000-2004) was obtained from the Centers for Medicare and Medicaid Services (CMS). Under a 1998 CMS initiative, the states are required to resolve deficiencies causing actual harm to residents within 30 days and deficiencies not causing actual harm within 60 days. We explored whether the states met these federal guidelines and identified predictors of deficiency resolution (demographics, elected officials, industry characteristics, etc.), using the linear mixed model. While nearly all the states resolved non-actual harm deficiencies within the 60-day grace period, only one state (Tennessee) resolved actual harm deficiencies within 30 days, as required by the CMS. State-level factors that predicted faster deficiency resolution were chain ownership of facilities and greater influence from the nursing home industry. In contrast, a higher ratio of registered nurses to nursing home residents in a state was associated with slower deficiency resolution. The federal requirement for states to correct their most serious nursing home problems within 30 days is problematic. On average, 49 of 50 states were unable to meet this objective. In addition, quicker turnaround is found in states where for-profit nursing homes are strongest. This suggests that faster resolution of deficiencies may be of greater benefit to the nursing home industry than to nursing home residents. © 2008, Hallym Aging Research Institute, Hallym University.