Hepatitis C is the silent epidemic of the 1970s and 1980s. Interferon alfa is currently the only effective treatment. Enthusiasm for interferon therapy must be tempered because advanced disease usually requires years or even decades to develop and does not occur in all patients. Few patients with chronic hepatitis C derive long-term improvement from a single 6-month course of interferon therapy. Most initial responders relapse and require long-term interferon treatment to suppress the virus. Obviously, the initial goals and expectations for interferon therapy require rethinking. Therapy should not be undertaken by physician or patient with the idea that therapy will be limited to 6 months. The most appropriate goal of therapy now appears to be the long-term control of the biochemical, virologic, and histologic activity of the disease. Unfortunately, the most effective therapeutic regimen for achieving this goal is not yet known and will require continued clinical research.