Climate change, reduced air quality and stratospheric ozone layer destruction are large societal challenges that are caused by anthropogenic emissions. To assess the impact of these emissions on the atmospheric composition, satellite observations with global coverage and frequent revisit times are essential. Over the last two decades, satellite remote sensing of the atmospheric composition has developed rapidly; both the number of relevant atmospheric species that can be observed, as well as the quality of the data have strongly increased. One of the leading instruments in this field is the Ozone Monitoring Instrument (OMI), the Dutch-Finnish contribution to the NASA Aura mission, which was launched in 2004 and is still operational. OMI is a nadir viewing ultraviolet and visible spectrometer that measures several trace gases includes ozone, nitrogen dioxide, sulfur dioxide formaldehyde as well as aerosol and cloud properties. OMI is the first instrument of its kind to combine daily global coverage with high spatial resolution of 13x24 km at nadir. Examples of OMI data utilization are: process studies to improve chemical transport models, quantification of emission sources, data assimilation for numerical weather prediction and air quality forecasting, and volcanic ash warning systems for aviation safety. The follow-on instrument for OMI is the TROPOspheric Monitoring Instrument (TROPOMI) on the ESA Sentinel-5 Precursor planned for launch in 2014. TROPOMI will be the first in a series of European satellite sensors dedicated for monitoring atmospheric composition changes in the timeframe 2015-2030. The TROPOMI instrument has a heritage to both OMI and for SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY). Compared to OMI, TROPOMI is extended with spectral bands in the near infrared and in the shortwave infrared, which will enable detection of carbon monoxide and methane. With a spatial resolution as high as 7x7 km, higher signal-to-noise and extended spectral coverage, TROPOMI will provide exciting new information on the changing composition of the troposphere. In this contribution an overview will be given of successes of OMI for atmospheric composition monitoring and research. In addition, an outlook will be given of the enhanced observational capabilities of TROPOMI.->