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The X-ray emissions from exoplanet host stars are a key to understanding the evolution of planetary atmospheres. We propose X-ray and UV observations of 7 stars known to host multiple transiting super-Earths. The data will be combined with transit spectroscopy and synthesised EUV spectra to provide the crucial input for detailed atmospheric modelling. The proposed observations will almost double the sample of super-Earths with well characterised XUV radiation environments. The highest priority target is K2-18 which is the first exoplanet where the signature of water has been detected in its atmosphere. This study is designed to answer key questions about exoplanet atmospheres comma including their evolution comma evaporation comma photochemistry and production of biologically significant molecules.