CARMENES. I: instrument and survey overview Quirrenbach, Andreas Amado, Pedro J. and the CARMENES Consortium Paper 8446-25 of Conference 8446 Date: Monday, 02 July 2012 Talk CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs) is a next-generation instrument to be built for the 3.5m telescope at the Calar Alto Observatory by a consortium of eleven Spanish and German institutions. Conducting a five-year exoplanet survey targeting ~300 M dwarfs with the completed instrument is an integral part of the project. The CARMENES instrument consists of two separate échelle spectrographs covering the wavelength range from 0.55 to 1.7 mum at a spectral resolution of R = 82,000, fed by fibers from the Cassegrain focus of the telescope. The spectrographs are housed in vacuum tanks providing the temperature-stabilized environments necessary to enable a 1m/s radial velocity precision employing a simultaneous calibration with an emission-line lamp.