The XENON100 experiment searches for the interactions of weakly interacting massive particles (WIMPs) in a target of 62 kg of liquid xenon. Situated in the Laboratori Nazionali del Gran Sasso (LNGS), it is the most sensitive dark-matter detector to date. Published results from a search based on 225 live days of data show no indication for dark matter, but the derived upper limits are the most stringent to date for WIMP masses above 7 GeV/c². The development of XENON1T, which will be about 35 times larger, is also underway. The aim is to reach a dark-matter sensitivity that is two orders of magnitude better.