Patients with Primary insomnia often experience intrusive, worrisome cognitive activity in the pre-sleep period. Metacognitive beliefs may explain this yet no valid reliable scale exists. The present study, therefore, developed the Metacognitions Questionnaire--Insomnia (MCQ-I). Following initial metacognitive insomnia profiling interviews, item refinement produced a preliminary 60-item MCQ-I. This was administered to 34 primary insomniacs and 37 normal sleepers. Psychometric data indicate primary insomniac patients score significantly higher than normal sleepers on MCQ-I. Test-retest reliability is good. Face, concurrent, construct and discriminant validity, scale sensitivity and specificity are all acceptable. Further research with larger primary insomnia and normal sleeper samples is now required.