Quantum dots (QDs) represent a unique subset of nanomaterials characterized by their quantum confinement behavior. Most notably this manifests itself in nanocrystalline semiconductor materials which below a critical dimension (particle size typically < 10 nm), and in contrast to their bulk form, exhibit a remarkable transformation in optical, electronic or magnetic property behavior. From an applications/device perspective they can be predictably tuned according to their size, shape and intrinsic solid state properties. Originally exploitation of this unique behavior was limited to the fabrication of solid state electronic and optoelectronic devices incorporating, for example, epitaxially grown QDs. More significant however has been the recent advent of wet-chemically synthesized QDs, available in a colloidally dispersed form making them amenable to ink jet printing as well as other liquid deposition technologies. These colloidal products now promise to open up commercial opportunities for a myriad of new uses.