Résumé
The Cherenkov Telescope Array (CTA) will be the world's largest and by far most sensitive observatory for high-energy gamma rays. It will be capable of detecting gamma rays from extremely faint sources with unprecedented precision on energy and direction in the energy range from 20 GeV to more than 300 TeV. The performance of the future CTA observatory derived from detailed Monte Carlo simulations is presented in this contribution for the two CTA sites in Paranal (Chile) and on the La Palma island (Spain).