Computer-assisted cognitive-behavior therapy, a treatment that has been shown to be effective in previous studies in psychiatric settings, will be disseminated into primary care - a health care setting where there are significant problems in receiving adequate treatment for depression. Computer-assisted cognitive-behavior therapy will feature a low-cost method of delivering therapy designed to be replicated and sustained in other primary care settings. Feasibility and effectiveness will be tested by randomly assigning 320 primary care patients with depression to receive either computer-assisted cognitive-behavior therapy or treatment as usual.