The implementation of the disease management programme (DMP) for asthma and COPD in the German health system in 2005 requires an optimal and evidence-based work-up of patients by general practitioners in routine daily practice. The German and international guidelines for COPD do not provide recommendations for a stepwise diagnostic work-up in primary care. Therefore, an evidence-based algorithm was developed for a stepwise diagnosis of COPD and its different stages in general practice, based on national and foreign guidelines that provide specific advice on diagnostic procedures.