What has been happening in East Germany since the construction of the Berlin Wall is the main subject of this detailed and thorough report by a well known journalist. In the 20 years since the end of the war the ""German Democratic Republic,"" with its 17 million people compared with West Germany's 56 million, has managed to become one of the world's leading industrial powers, ranking first in industrial output, in the Communist world, after the Soviet Union. The price of rapid industrialization, of course, has been chronic shortages and a depressed standard of living. Instead, however, of the mass dissatisfactions pictured by Western propaganda, Hangen finds that East Germany's new leadership--the industrial managers, professors of economics, younger party men--are committed to making communism work in their part of Germany and are now concentrating more on pragmatic economic reforms than on the ideological transformation of society. The ""apostles of the new economic order"" are more adventurous and more willing to experiment than their still undisputed ""boss,"" the doctrinaire Ulbricht whose ideological ties to the Soviet Union are viewed as a hindrance to the development of East German progress on several fronts. Hangen sees no forthcoming alteration, however, in the division of the two Germanys. The status quo suits Moscow and Washington accepts it in the absence of a more positive policy. Hangen's book is illuminating and does much to clarify a complicated situation, but his routine presentation is an obstacle to overcome.