PURPOSE: This clinical replication series assessed the perceived outcome of individuals with chronic insomnia who spontaneously sought treatment at a hospital behavioral-medicine insomnia program. PATIENTS AND METHODS: Chronic insomnia patients who were treated with a group multifactor behavioral intervention completed posttreatment (n = 102) and 6-month follow-up (n = 70) questionnaires that assessed improvement. RESULTS: All patients reported improved sleep at posttreatment, with the majority (58%, 59) reporting significant improvement. Of sleep medication users, 91% (62/68) either eliminated or reduced medication use. At B-month follow-up, 90% (63/70) of respondents rated improvement in sleep as either maintained or enhanced. CONCLUSION: These results suggest that patients spontaneously seeking treatment for insomnia, including sleep medication users and those with psychological comorbidity, derive significant benefit from a group multifactor behavioral intervention. Several factors, including maintenance of therapeutic gains at long-term follow-up, the average pretreatment duration of insomnia, previous unsuccessful treatment with psychotherapy and pharmacotherapy, and previous research, argue against nonspecific effects playing a significant role in these results.