The nanomaterials library – consisting of building blocks that are confined to less than 100 nm in 1, 2, or all 3 dimensions – is vast, and constantly growing. When at these length scales, materials behave differently than their bulk counterparts. For example, semiconductor nanocrystals feature size-tunable band gaps, and metallic nanocrystals support localized surface plasmon resonances which allow for light confinement far below the diffraction limit. One of the grand challenges in nanomaterials is how to assemble engineered structures from these materials in ways that utilize their unique properties. In this dissertation, we make use of two different templated assembly techniques to this end: we use capillary-driven template-assisted self-assembly to define individual nanostructures comprised of small numbers of nanocrystal building blocks in lithographically defined templates, as well as an emulsion-based self-assembly approach, where an oil-in-water droplet serves as the template, to construct well-defined superparticles from ensembles of semiconducting nanocrystals. Given their small size, interrogation of the optical properties of these structures, as well as those of their constituent nanomaterials, requires unique spectroscopic tools. Here, we describe the construction of two home-built, spectrometer-coupled, stage scanning confocal microscopes which allow us to collect spatially resolved spectral data (down to temperatures of ~13 K). We use these tools to interrogate plasmonic enhancement of individual upconverting nanophosophors, Raman scattering and photoluminescence from 2D perovskites, and lasing properties of superparticles composed of CdSe/CdS nanocrystals. In the case of the superparticles, we show that while the lasing modes are not initially stable, light soaking at high fluence imparts a high degree of temporal stability (reducing frequency shifts to 1.7 ± 0.5 meV over 15 minutes of continuous operation). We also demonstrate optically controlled, color-tunable lasing in these superparticles, whereby the pump fluence controls the color of SP lasing.