SIAPWS is the Nordic representative of IAPWS, the International Association for the Properties of Water and Steam, focusing on thermophysical and chemical properties of water and steam. SIAPWS deals with water chemistry and water treatment in the Nordic energy sector and related industries. SIAPWS is connecting national groups for exchange of experience in Sweden (Matarvattensektionen), Finland (SIAPWS‐Suomi), and Denmark (SIAPWS‐Danmark).