OBJECTIVES: Early morning symptoms (EMS) of COPD are associated with poor health, impaired daily activities and increased exacerbation risk. We describe the development and preliminary validation of the Manchester Early Morning Symptom Index (MEMSI) to quantify EMS in COPD. METHODS: Potential items were identified from interviews and focus groups with COPD and non-COPD participants. Cognitive de-briefing elucidated the relevance and understanding of the potential items followed by a cross-sectional study to finalise the items for inclusion. The draft scale was completed twice, one week apart to assess test-retest reliability. The St George’s Respiratory Questionnaire (SGRQ), modified MRC Dyspnoea Scale, FACIT fatigue scale and Hospital Anxiety and Depression Scale (HADS) evaluated convergent validity. Hierarchical methods and Rasch analysis informed item reduction and assessed uni-dimensionality. RESULTS: