During Stage 3, 112 clients will participate in a randomized clinical trial (RCT) of the intervention (MFI). These participants will complete a baseline ASI6, as well as brief research assessments at 1-month post study intake and 2 months later (i.e., at the conclusion of their participation). They will also provide samples for UDSs. Clients will be randomized so that one-half will receive treatment as usual (TAU; with the exception that counseling sessions will be digitally recorded), and one-half will receive MFI. Clients in the MFI group will participate in standard treatment and complete the MMI weekly with their counselors at the beginning of each individual counseling session. Also, a total of 8 counselors will be randomly selected to participate. They will be randomized so that 4 will provide TAU, and 4 will provide MFI. All counselors will meet with research staff for training and to periodically complete questionnaires/interviews. All individual counseling sessions will be recorded using a digital voice recorder.