The integration of metallic and dielectric building blocks into optoplasmonic structures creates electromagnetic systems in which plasmonic and photonic modes can interact in the near-, intermediate-and far-field. The electromagnetic coupling between multiple building blocks in hybrid structures provides a multitude of opportunities for controlling electromagnetic fields in both spatial and frequency domain as well as for engineering the phase landscape and the local density of optical states (LDOS). Control over any of these properties requires, however, rational fabrication approaches that can integrate the different building blocks into hybrid structures with defined morphology. Template-

guided self-assembly strategies have been demonstrated to facilitate the assembly of a wide range of discrete optoplasmonic structures as well as optoplasmonic arrays or metasurfaces. We focus here on two fundamental strategies to control the photonic environment around plasmonic nanoantennas. In discrete optoplasmonic atoms or molecules optical microcavities (OMs) serve as whispering gallery mode (WGM) resonators that provide a discrete photonic mode spectrum. In extended hetero-nanoparticle arrays, on the other hand, in-plane scattered light can induce coherent interactions between the nanoparticles that result in geometrydependent resonances. The electromagnetic field of these photonic modes interacts with the localized surface plasmon resonances (LSPRs) located at the metal nanoparticles. We characterize the fundamental working principles of both optoplasmonic approaches and review template-guided self-assembly methods that facilitate their fabrication.