The nitrogen-vacancy (NV) centers in diamond is a promising solid- state qubit for emerging quantum technologies, due to its long spin coherence time and fast manipulation rates, together with a level structure that allows for straightforward optical initialization and read- out of the electronic spin state . In high-quality single-crystal diamond at temperatures below 25 K, sharp zero-phonon-line (ZPL) optical transitions facilitate the coherent coupling between NV-center spins and photons. In this dissertation, I describe several experiments which explore the local spin environment around the NV centers along with a technique of electrically controlling their spin fine structure. We also take a bottom-up approach, by growing diamonds specifically engineered with shallow NV centers with long spin coherence times. The latter part of the dissertation explores two ways of manipulating the NV centers using all-optical control techniques, eliminating the need for traditional electron spin resonance devices and increasing the scalability and integration of NV centers into photonic networks.