Optoelectronic packaging is the art of turning well-performing demonstrators of working principles into real devices, so as to guarantee required performances, reliability and cost-effectiveness. To this complex aim, packaging leads many heterogeneous disciplines to convergence, spanning from optics to mechanics, to electronics and material science. Optoelectronic packaging issues and solutions strongly differ, depending on the nature of the system to be implemented and on its level of integration. Three different cases of optical systems for telecomm applications will be discussed, respectively representing on-package integration, on-board hybrid integration and on-chip integration of a monolithic silicon-optics subsystem.