Research Area C embraces projects where the interactions between the individual constituents are engineered. This includes the exchange of photons and a direct matter-matter coupling by quasi static electric and/or magnetic interactions. The cooperative response is then observed in the spatiotemporal structure of the emitted electromagnetic radiation. The corresponding signatures of cooperative behavior are the observation of super- and subradiant emission, the onset of spatio-temporal photon correlations including the emission of non-classical light. Research Area C investigates furthermore the impact of different dimensionalities, geometries, in the presence of disorder, and of the boundary conditions on the cooperative behavior of its platforms. In particular, structuring of media, control of thermal fluctuations and control of the coupling to the environment allows for a detailed analysis of the impact of noise, fluctuations, and dissipation on the coopertive response of the systems.