It has been 20 years since we fi rst set foot on the journey that has become the third edition of the Encyclopedia of Special Education. If someone has told us then that we would end up chronicling the evolution of special education, we probably would not have believed him or her. It was enough, at that time, to have created the fi rst Encyclopedia of Special Education; nearly 2,000 pages, thousands of entries, and more than 400 authors coming together to cement this fl edgling fi eld that was full of hope and imagination. So, here we are more than 20 years later, near the end of our guardianship of the Encyclopedia. It is our old friend, and it has been our mentor, our judge, and our inspiration. During the editing of the second and third editions, we are well aware of how life, research, and standards have changed for those of us who practice in special education. It is an interesting process to look back and see how the Encyclopedia has changed over the years and how it has really provided a mirror of the zeitgeist of the times in which we live.