The days of confident clarity of purpose and action in the field of special education in the United States are behind us. In the 1970s and 1980s, a relatively young profession bolstered by new federal legislation and astronomical growth in the numbers of professionals burst forward with tremendous optimism. The reasons for this wide-eyed optimism were many. Legal battles over the rights of students with disabilities had resulted in not only court victories breaking down walls of segregation but also a federal law mandating the education of all children regardless of disability. Funding for research, training, and program development initiatives flowed freely. And a new science called "behavior modification" was coupled with an old science of psychological measurement to form what appeared to be a promising knowledge foundation for the expanding and hopeful field. But the optimism of a youthful profession soon transformed into the complexity and conflict of adolescence. In the 1980s and 1990s, special educators realized that the victory of a guaranteed education for all students had been only a defeat of segregation. Public education was very willing to segregate within the boundaries of public schools by excluding students with disabilities from general buildings and classrooms. The attention of many special educators turned to the new antisegregation movement--inclusive education. Yet even this goal divided special educators into two groups: those who sought the radical reform of public schools and communities and those who sought politically milder objectives concerning student performance and skills. Simultaneous to the inclusion debate was the serious questioning of the optimistic sciences of psychological measurement and behavioral technology and the practical value, political leanings, and theoretical meaning of these knowledge bases. Issues concerning quantitative and qualitative research methodologies were just the "tip of the iceberg" as the field ruminated over deep philosophical questions about science and belief. By the turn of the century, one could look back to view the simple clarity of purpose and professional practice that marked the field of special education during the 1970s and most of the 1980s as a brief stage of innocence in the historical development of this field.What to doandwhy to do itwere questions that seemed neatly settled to the young profession. From that ostensible consensus, it seemed that this profession could move forward toward lofty goals for students and families. By the beginning of the twenty-first century, these very questions--ethical, practical, and political--are open to examination, critique, and discussion across the profession. The most recent development in this brief history of modern special education is what we callthe challenge of disability studies.Quite simply, people with disabilities have united in many quarters to question the ways that they are understood and treated by the nondisabled majority, including the nondisabled professionals who make up special education, rehabilitation, and the other disability service fields. While the young field of special education put much emphasis on viewing human activity and identities from the standpoint of an objective science touted as unbiased and accurate, disabled scholars, writers, and activists have questioned the inherent ableism and overwhelming power of the perspective of the nondisabled professional fields. Who gets to define the meaning of disability? Can one truly understand disability if one does not have a disability? Can a nondisabled person claim to hold an objective, unbiased perspective on a way of living that is foreign to his experience? What kinds of ableism hide behind the social sciences and professions that claim to have the best knowledge of disability? These questions and others are now at center stage as special education and the disDanforth, Scot is the author of 'Crucial Readings in Special Education', published 2003 under ISBN 9780130899293 and ISBN 0130899291.