Marco Bersanelli is Associate Professor in Astrophysics at the University of Milano, Physics Department. He works in the field oj observational cosmology. in particular on observations Cosmic Microwave Background (CMB) radiation. He graduated in Physics at the University of Milano in 1986 and worked in the Astrophysics group at the Lawrence Berkeley Laboratory, University of California, until 1991. He designed and built microwave radiometers for CMB experiments in the 1–90. GHz range and participated in a number of observational campaigns from the White Mountain High Altitude Research Station, University of California and from the Amundsen-Scott South Pole Station. Antarctica (1986–1992). He then worked as Research Staff and Senior Researcher at Istituto di Fisica Cosmica, Consiglio Nazionale Ricerche, Milano, Italy until 2000. Since 1992 prof Bersanelli has been deeply involved in the Planck Surveyor space mission, the European Space Agency project designed to produce high precision full-sky maps of the CMB temperature and polarisation. He was a member of the Planck Assessment Study Team (1993–94) and of the Planck Phase A Science Team (1994–96). He has coordinated the design of the Planck Low Frequency Instrument (LFI), a radiometer array based on cryogenic HEMT ultra-low noise transistor amplifiers. Within the Planck Collaboration he participated in various working groups and activities including instrument and telescope design and optimisation. thermal design of the spacecraft, on-ground and in-flight calibration, study of systematic effects and their scientific impact on the survey data, simulations and preparation for the Planck data processing. He is currently Instrument Scientist of LFl and a member of the Planck Science Team. Prof Bersanelli is also involved in sub-orbital CMB experiments such as the Background Emission Anisotropy Scanning Telescope. Other research interests include measurements and analysis of galactic diffuse radio emissions, in particular synchrotron and free-free radiation; multi-frequency observations of active galactic nuclei; observations and modeling of atmospheric emission in the microwaves.