A wide range of gravitational wave detectors is currently operating, and in a few years will reach a sensitivity enabling them to potentially detect sources tens of megaparsec away. In the next years, the instruments will be upgraded, giving birth to a new generation of improved, more sensitive detectors. Alternative techniques are also being explored which have the potential in a longer term of even better sensitivities. Such improvements are needed to turn a still elusive hunt for a first detection into a real gravitational-wave astronomy; it is the purpose of this talk to outline the path toward the design and realization of advanced detectors, and to discuss how they will be integrated into a global network.