The environments of some agencies are more political, more volatile, and more tumultuous than those of others. The Bureau of Engraving and Printing and the U.S. Geological Survey lead much more serene political lives than do the Environmental Protection Agency and the Federal Communication Commission. But whatever the conditions, the environment in which an agency exists may contain many forces that may, at one time or another, impinge on it and help give direction to its actions in multitudinous ways.“ These forces may arise out of the following sources.