The formation and evolution of field massive galaxies

The problem of the formation and evolution of field massive galaxies is briefly reviewed from an observational perspective. The motivations and the characteristics of the K20 survey are outlined. The redshift distribution of K _s<20 galaxies, the evolution of the rest-frame K _s-band luminosity function and luminosity density to z∼ 1.5, the nature and the role of the red galaxy population are presented. Such results are compared with the predictions of models of galaxy evolution. This revised version was published online in July 2006 with corrections to the Cover Date.