In the Netherlands, the majority of patients (60-80 %) with asthma or COPD are treated in primary care, primarily by General Practitioners (GPs). In 1995 a Regional Diagnostic Centre, Etten-Leur, The Netherlands (also called SHL: Stichting Huisartsen Laboratorium) started a lung function monitoring service for patients with asthma and COPD of GPs in the region. The GP receives recommendations on treatment, additional diagnostics and referrals of the patient based on extensive anamnesis (i.e. dyspnoea, symptoms, smoking stage), measurement of lung function, and BMI. Moreover,the general practitioners are supported by an Asthma/COPD nurse that visit the general practice half-yearly.