The aim of HITRAN (high-resolution transmission molecular absorption database) was to characterise the amount and wavelength-dependence of absorption by water vapour and other atmospheric species. It was part of the Natural Environment Research Council (NERC) funded Clouds, Water Vapour and Climate (CWVC) program. The dataset contains spectral line parameters derived from laboratory measurements on pure water vapour, and mixtures of water vapour and air. The measurements were made at STFC Rutherford Appleton Laboratory Molecular Spectroscopy Facility, and the line fitting was carried out by the Department of Meteorology at the University of Reading. The spectral line parameters are displayed in HITRAN format. Water vapour lines were fitted to the laboratory data in the spectral range 5037 to 5585 cm-1. These data are public.