​​The Molecular Spectroscopy Facility (MSF) is a world-class facility for the UK environmental science community to conduct a wide range of interdisciplinary research. It provides central laboratories, scientific equipment, training, scientific/technical support, and high-quality data. Through the MSF, broadband, high spectral resolution Fourier transform, and fibre-optic spectrometers are available for measuring the absorption, emission, and scattering properties of solid, liquid, gas/vapour, and aerosol samples contained in a range of spectroscopic cells. High-quality spectroscopic data over the entire spectral range from wavelengths (wavenumbers) of 1 mm (10 cm^-1) in the far-infrared/sub-millimetre range to 180 nm (55,000 cm^-1) in the far ultraviolet are generated at spectral resolving powers of up to 1 part in a million and time resolutions as high as 5μs. Customised sample cells are available for specific temperature-dependent measurements over the range 77 to 350 K at optical path-lengths from 1 mm to over 1 km using multi-pass optical systems. For atmospheric chemistry studies, the chemical synthesis area and laser-safe laboratories permit a wide range of projects to be supported.