School systems around the United States are heavily segregated by income and race. At the same time, an achievement gap between white and nonwhite students persists despite many efforts to close it. Against this background, in this white paper the authors explore the history and successes of the Metropolitan Council for Educational Opportunity program, better known as METCO. The paper begins by examining segregation in the United States and in Massachusetts. [This white paper contains a preface by Gerard Robinson.]