Physics with the CMS Experiment in the First Year of LHC

The preparations of the CMS collaboration for first data taking, when the Large Hadron Collider (LHC), located close to Geneva, Switzerland, starts to circulate and collide proton-proton beams at center-of-mass energies around 14 TeV in 2007, are presented. This new and unexplored energy domain will provide unique opportunities to search for new physics at the TeV scale, a preferred region for many extensions of the Standard Model. The status of the CMS detector and the possible impact of staging on the physics program are presented, followed by a description of the main data samples and their use for alignment and calibration. Selected search channels and signatures for Higgs bosons, Supersymmetry, Extra dimensions and Contact interactions will be discussed.