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Superconductivity is a phenomena that would likely never have been predicted by theory in the absence of the experimental discovery [1,2] because it depends on the seemingly unlikely scenario of two electrons being attracted to each other. For nearly a century, this exotic low-temperature phase has attracted considerable interest in large part due to the, as yet unrealized, promise of room-temperature superconductivity and its many potential applica-tions. While we now have a basic theoretical understanding of superconductivity [3], from a practical standpoint, theory has yet to prove successful in bringing superconductivity closer to room-temperature. Systematic experimental studies, both through chemical substitution and high pressure, are still the primary means of discovering higher temperature supercon-ductors. In this dissertation I will describe the results of ultra-high pressure experiments (up to 1.7 Mbar) on pure elements, alloys and compounds. A variety of probes including resistivity, ac magnetic susceptibility and optical spectroscopy are used to investigate the optimal conditions for high superconducting transition temperatures. i Acknowledgements I offer my most sincere thanks to: My advisor, Dr. Jim Schilling, whom it has been a privilege to work for. I can not thank you enough for the experience I have gained as your student. Dr. Anne Hofmeister, for generously donating her time, equipment and expertise to make the infrared absorption measurements possible. Dr. Vladimir Tissen for many informative discussions and for first suggesting that we examine yttrium. The members of my dissertation committee, for helpful discussions and enlight-ening answers. Julia Hamilton, for reminding me, with good humored insistence, to take the necessary steps to actually graduate. Dr. A. Gangopadhyay for assistance with the PPMS measurements