I worked on several aspects of the design of Planck, from the scanning strategy to the minimization of straylight contamination. I demonstrated the feasibility of total power measurements with Planck (as opposed to differential measurements such as those of COBE and WMAP) with minimal impact of detector low-frequency noise. I also participated in the early observations of the SZ effect from galaxy clusters with the Diabolo experiment. My PhD supervisors were Jean-Loup Puget and David N. Schramm.