Abstract : This is the final report for the AFRL/RI in-house project Quantum Information Science. Under this project we constructed a six qubit (quantum bit) capable photon-based experimental testbed for the development of photon-based quantum gates and circuits and performed experimental and theoretical investigations of quantum computation. These investigations included: theoretical/numerical simulation: (1) a hybrid coarse/fine parallel simulation of Grover's quantum search algorithm; (2) the development of a variant of Grover's algorithm that explicitly searches on one component of a database; (3) the design of quantum optical gates by means of volume holography in photo-thermal refractive glass, and (4) an investigation of the advantage of utilizing cluster states for a one-way quantum computational paradigm; experimental: (5) the construction and validation of a group velocity matched temporal compensator crystal assembly to increase the usable range of entangled photon sources, and (6) the development and characterization of a new multipli-entangled photon source that increased the usable number of photon pairs by a factor of six.