The 2009 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension (PH) have been adopted for Germany. Invasive hemodynamic data obtained by right heart catheterization are essential to confirm the diagnosis, test vasoreactivity, assess severity and guide therapy in PH patients. The definition of PH is resting on a mean pulmonary artery pressure ≥ 25 mm Hg obtained by right heart catheterization. Furthermore, a pulmonary capillary wedge pressure > 15 mm Hg excludes pre-capillary PH. Vasoreactivity testing is part of the diagnostic work-up in pulmonary arterial hypertension. Recent data on the use of inhaled iloprost update these guidelines and are of special importance due to the frequent diagnostic use of iloprost in Germany. Other aspects of invasive hemodynamic data in certain PH subgroups as well as their measurement and interpretation in children are discussed. Several aspects of right heart catheterization in PH justify a detailed commentary, and in some areas an update already appears necessary. In June 2010, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Paediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups were initiated, one of which was specifically addressing the invasive hemodynamic evaluation of patients with PH. This commentary summarizes the results and recommendations of this working group.