Adults (ages 18+) who would like to reduce their cannabis use (N=224) will be enrolled in an 8-week treatment program. All participants will receive counseling (1 goals session with a therapist followed by 7 weekly computerized cognitive-behavioral therapy sessions). Detailed cannabis assessments (biological and self-report) will be conducted throughout treatment and at 1-, 2-, and 3-months post-treatment completion. Daily electronic diaries will be administered via text message to record detailed logs of cannabis use quantity and frequency. Salivary samples will be collected (and video observed) daily throughout treatment to analyze for progesterone.