The ability to confine light in three dimensions has important implications for quantum optics and quantum-optical devices. Photonic crystals, the optical analog of electronic crystals, provide us a means of achieving this goal. This analogy has motivated a whole new series of experimental and theoretical searches for elusive photonic band-gap structures. Combinations of metallic and dielectric materials can be used to obtain the required three-dimensional (3D) periodic variation in the dielectric constant. This could pave the way for photonic crystal structures that have widespread applications.The working of 3D photonic crystals into the wavelength regimes where most optoelectronic devices operate, i.e., 1.3 to 1.5µm was explored in the course of the thesis work. Simulations were run simultaneously on samples that were considered using Multirad. A one to one correspondence was sought between the two, i.e., experimental and simulated results. The basis for the conclusions was drawn from the known and present experimental results and simulations. The need for research on photonic crystal structures in particular areas was evaluated. Inferences drawn from this were then deployed to identify areas of modem science that would benefit from discoveries in photonic crystals.