This review covers the hard to heal wounds which appear frequently and require a complex time-consuming and resource-demanding treatment. The pathogenesis is often multifactorial and oxygen supply to the ulcer and its surroundings is an essential player in the healing process. Treatment should focus on identifying and optimising the global factors while simultaneously handling the local factors (oxygen supply in the tissue by relieving the pressure and reducing oedema and infection). Cross-disciplinary and cross-sectional cooperation is necessary in order to prevent, treat and rehabilitate the patients with hard to heal wounds.