As interesting as watching what happens to government when confronted with program planning is observing what happens to program planning when confronted with government. In August 1965, President Johnson called a breakfast meeting of his Cabinet officers and informed them that he was ordering a Planning-Programming-Budgeting System (PPBS), which had shown promising results in the Pentagon, installed throughout the rest of the Executive Branch. Inquiring reporters were told by government officials that shortly we could establish the relative pay-offs of, say, building a dam in Florida, or improving Indian schools, or eradicating syphilis. Henry Rowen, formerly of the Pentagon and now president of the Rand Corporation, was installed as Assistant Director of the Budget Bureau, whence he dispatched skilled program planners throughout the nervous and dubious government agencies. Two years and several attempts at PPBS studies later, the most thoughtful practitioners of the art are arriving at a considerably narrower– though probably no less significant– definition of the possible, and of where PPB’s most valuable contributions might lie.