"Exceptionally luminous and active galaxies are cosmic laboratories in which familiar astrophysical processes such as star formation can be studied in extreme environments and under extreme conditions. At the same time, relativistic phenomena, such as mass accretion onto supermassive black holes and launching of relativistic jets, are encountered and can be studied on mass and spatial scales many orders of magnitude higher than their stellar-remnant counterparts. Here, we propose a four-year joint programme between the Astrophysics Group at FORTH in Greece, the Max-Planck Institute for Radioastronomy in Germany, and the California Institute of Technology in the United States, with the aim to strengthen existing collaborations and create a lasting partnership between our institutions for the observational and theoretical study of the astrophysics of all modes of energy release in luminous and active galaxies, including those associated with the central supermassive black hole, and those associated with star formation. To this end, we propose a series of research staff exchanges and networking activities, with the following objectives: (a) strengthen existing collaborations and promote an enhanced effectiveness and productivity in our ongoing efforts; (b) explore further topics of possible collaboration based on the complementarities in the expertise of researchers in our institutions; (c) achieve mutual transfer of knowledge through the training of young researchers, seminars, and workshops; and (d) cement a long-term, sustainable collaboration between our three institutions. Our programme features complementary observational and theoretical parts, and specific tasks involve the radio, optical, and gamma-ray monitoring of blazars, including polarimetric studies; the X-ray studies of active galaxies with the upcoming NuSTAR mission; infrared studies of ultra-luminous galaxies with Herschel; and the theoretical modeling of blazar jets and star-forming regions."