Twenty‐nine insomniacs underwent four consecutive sleep laboratory evaluations before and after receiving tension‐release relaxation training, no‐tension‐release relaxation training, or no‐treatment. On the basis of the discrepancy between subjective and EEG‐defined measures of latency to sleep onset, subjects were classified as pseudoinsomniacs or idiopathic insomniacs. As predicted, tension‐release relaxation was significantly more effective than the other two conditions on subjective sleep measures, regardless of insomnia subtype and on objective sleep measures only for idiopathic insomniacs. Subjective improvement was maintained at 12‐month followup. Numerous differences between the two subtypes emerged on pretherapy and during‐therapy measures distinct from the latency measures, but changes on those variables were unrelated to ou