The present study evaluated an internet-delivered pain management program, the Pain Course, when provided with different levels of clinician support. Participants (n = 490) were randomised to 1 of 4 groups: (1) Regular Contact (n = 143), (2) Optional Contact (n = 141), (3) No Contact (n = 131), and (4) a treatment-as-usual Waitlist Control Group (n = 75). The treatment program was based on the principles of cognitive behaviour therapy and comprised 5 internet-delivered lessons provided over 8 weeks. The 3 Treatment Groups reported significant improvements (between-group Cohen's d; avg. reduction) in disability (ds ≥ 0.50; avg. reduction ≥ 18%), anxiety (ds ≥ 0.44; avg. reduction ≥ 32%), depression (ds ≥ 0.73; avg. reduction ≥ 36%), and average pain (ds ≥ 0.30; avg. reduction ≥ 12%) immediately posttreatment, which were sustained at or further improved to 3-month follow-up. High treatment completion rates and levels of satisfaction were reported, and no marked or consistent differences were observed between the Treatment Groups. The mean clinician time per participant was 67.69 minutes (SD = 33.50), 12.85 minutes (SD = 24.61), and 5.44 minutes (SD = 12.38) for those receiving regular contact, the option of contact, and no clinical contact, respectively. These results highlight the very significant public health potential of carefully designed and administered internet-delivered pain management programs and indicate that these programs can be successfully administered with several levels of clinical support.