This paper summarises the status of the European Space Agency’s programme for observation of the composition of Earth’s atmosphere: the three large spectrometers GOMOS (Global Ozone Monitoring by Occultation of Strars), MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) and SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY) onboard Envisat (ENVIronment SATellite) since 2002, the opportunities in the Earth Explorer research programme and in the Earth Watch programme for operational missions in cooperation with European Union ‘Global Monitoring for Environment and Security’ (GMES) or Eumetsat. Two studies on molecular spectroscopy commissioned by ESA (European Space Agency) and targetted at the needs of potential ESA space instrumentation are reviewed. One of them addresses mainly the temperature-dependent measurement of collisional linewidth parameters in the mm/sub-mm wave range and the setup of a spectroscopic dataset dedicated to a possible future limb-sounding instrument; the other aims to establish the feasibility of a high accuracy determination of absorption cross sections of water vapour in the near infrared for a potential future H2O lidar instrument.