5 C.F.R. § 792.104
Responsibilities of the Office of Personnel Management
OPM shall provide overall leadership for the Government-wide alcoholism and drug abuse program in cooperation with the Secretary of Health and Human Services. To accomplish this, OPM shall develop and issue policy and program guidance, provide technical assistance to agencies, and determine the overall effectiveness of the Government-wide program, as well as those programs at individual agencies, based on program information required of agencies.