High Contrast Imaging with Extreme Adaptive Optics

In the last 3 years, extreme adaptive optics (XAO) systems entered into operation. They explore a new regime in terms of inner working angle and contrast. After introducing the science case and technical requirements, we will review the architecture of XAO systems, before presenting a few selected science highlights obtained on disks and planet formation with instruments such as SPHERE, GPI, SCEXAO and MagAO.Acknowledgments: D. Mawet, D. Mouillet, A-M. Lagrange, J-L. Beuzi