Who holds power in the American system of government?"" asks Mr. Cater--and, with at least equal interest, how and why? As a writer for The Reporter, his approach might be termed hard-line liberal; within it, as he freely admits, he has not managed to cover all the important areas on the Washington scene, and even those which have been included here are seen with certain inherent ""risks"", because journalists ""must rely on makeshift theory"" and thus have ""trouble with the larger story of government"". Mr. Cater's study is divided in six sections, dealing with the Constitutional basis, the Presidency, Congress, the loss of role by the political parties, the modern types of lobbyists, and at the close- ""The Struggle to Govern"". This is a brief recapitulation and demonstration of the interaction of various power sources on each other. Cater is doubtful whether any of our ""ancient institutions"" can be ""reform by flat"" but all of them show ""disturbing evidence of power being exercised in unresponsive and irresponsible ways"". No simple solution is offered, but the situation has been made ominously clear... Mr. Cater is a judicious and cogent analyst (The Fourth Branch of Government- 1959), often original and steadily stimulating.