many of whom have followed and supported me through this process for a long time. I also want to thank Cleveland Shields, Ph.D. for the opportunity to work with and learn from him, and for his willingness to share his research with me. I especially want to thank Ron Werner-Wilson, Ph.D., who took me in and agreed to help when I was in a very down part of my life. He has been incredibly supportive, encouraging and patient as I proceeded toward this goal. I am indebted to John Harvey, Ph.D., my first mentor and probably the one person, who, through all of this, never ever gave up hope that I would finish. Finally, John, I owe you lunch. I also thank my friends and coworkers for their support and encouragement, especially Jan Zrostlik, who was always willing to help by typing "an emergency page or two" and proofing this document. Last but by no means least, for my wife, Kim, and my son, Noah. Words cannot express the joy you have brought to my life. As we always said... Things happen for a reason, just believe.