Compact, efficient, high-quality and scalable non-classical photon sources are one of the most critical building blocks for quantum information processing and communications. Photon pair generation via spontaneous four wave mixing is being recognized as an attractive platform for quantum optics which is compatible with the rapidly-maturing classical integrated photonics technology using silicon wafers, which is adopted in industry for its low cost, high performance and scalability. Traditionally, the photon pairs generated from silicon photonic devices, however, have not compared favorably with traditional nonlinear crystals in terms of overall rate, quality and efficiency. This dissertation discusses the factors that affect the quality and efficiency of photon pair generation in silicon integrated photonic microrings, together with their design and characterization. Furthermore, we show how the microrings can be integrated with other photonic devices on the silicon-on-insulator platform, and using proof-of-concept experiments, discuss the feasibility of using these photon-pair sources with technology that is already present in, or will soon be present in, practical fiber-optic networks, such as integrated lasers and modulated classical data streams.