The programme originated from the International Hydrological Decade (IHD 1965-1974), becoming the International Hydrological Programme (IHP) in 1975. Since then it has considerably advanced on the methodology applied to hydrological studies and therefore refers to training and education on water sciences.
Although the programme general objectives still apply, recognising the role of water resources management in sustainable development and water sciences adaptation to changing weather and environmental conditions has become increasingly important over time. Integrating the underdeveloped countries in global research and training initiatives countries has been another significant development.
The activities of the IHP, which is a programme executed in 6-years phases, are conducted through working groups in symposia, workshops, publications and EXB projects, the latter carried out via the UNESCO Regional Offices where regional hydrologists work.