Build, not burn,"" is the standard for the Students for a Democratic Society and the Student Non-violent Coordinating Committee, if not for the other groups who make up the political phenomenon called the New Left. In the ""objective"" popular press hardly any attempts have been made to grapple with the underlying causes for this startling post Korean War social miracle. This history and appraisal of ""the Movement"" by twenty-six year old Jack Newfield, a founder of SDS and a partisan of SNCC, seems to prove the axiom that came out of the Berkeley Rebellion-- ""never trust anyone over thirty."" For where the press stops short, Newfield moves on. He makes clear the origins and motives of those thousands committed to equal rights and a moral foreign policy; he assays the conditions in American life which have made for the growth of such socialist-oriented, anti-totalitarian groups as SDS. Portraits of the leadership, Robert (Moses) Parris, Stokely Carmichael, Tom Hayden and others, lend, by their examples, to his thesis that these are the best young workers on the job of constructing tomorrow's America in good and meaningful ways. Sympathetic, but never uncritical, Newfield's first book--(his able articles have been appearing in the The Village Voice over the past two years) proves him a builder, a free and hardthinking young man whose company older liberal reporters ought to keep.