Photonic Crystals are the newest types of optical material being developed for commercial applications in industry. They are likely to provide an exciting new tool for the manipulations of photons and have received the attention of both academia and industry. Roadmap on Photonic Crystals gives a detailed explanation of the background of photonic crystals, the theories behind them, numerical simulations, crystal structures, fabrication processes, evaluation methods and proposed applications. This also includes a roadmap addressing future development and applications. Industrial scientists, post-doctoral researchers and graduate students will find Roadmap on Photonic Crystals a useful tool in the understanding of the critical aspects of photonic crystals.