The interim final rule provides guidance on implementing the Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act. It goes into effect on April 5th and applies to group health plans with 50 or more enrollees starting on or after July 1st. The rule divides benefits into six classifications and requires parity within each classification for mental health and substance use disorder benefits compared to medical/surgical benefits. It prohibits certain non-quantitative treatment limits for mental health/substance use disorders unless similar restrictions exist for medical/surgical benefits. The rule also prohibits separate deductibles, copayments, or out-of-pocket limits for mental health/substance use disorders and medical/s