In the first 200 pages of this book, the author presents six case studies from city politics in 1950s Chicago. As the author explains on page 6, these political situations may often be viewed as ones where a proposal is to be adopted or is not to be adopted. In each case study, the author describes in great detail how various people and committees exercised their political influence for and against certain proposals. In a 150-page theoretical summary at the end of book, he presents a general theory of political influence.

The case studies are boring. It's hard to imagine who would today be interested in reading such detailed accounts of how minor decisions in city development were taken in 1950s Chicago. The list of persons and committees involved in each decision is so long that the reader soon loses track of who is who and can't recall what the author wrote about the same person a few pages ago. After reading through a couple of these case studies, I decided to skip the rest.

The theoretical part is of course much more interesting. Political influence can, at least in city politics, work almost like a medium of trade, like currency in the marketplace. Various players in the political game possess varying capacities for exercising influence, but that does not mean that those who possess the most will take all decisions. Influence is a limited resource, so an agent who exercises a lot of influence on one proposal will have a lesser amount available for the next proposal. Influence-poor actors who care most about a given proposal may exercise more influence to get it passed than indifferent influence-rich actors will expend against it.

The final chapter of the book provides an interesting discussion on whether this sort of influence-balancing can generate a positive system of "social choice", where disagreements can be mediated more effectively than through central planning. This depends not only on how the political machine works, but also on the sources from which influence political actors can obtain their influence. At least in 1950s Chicago, influence sources included political elections, wealth, reputation and standing in local communities, and of course past usage of influence. The questions are very complex, but the case studies illustrate that the real world is also complex, and realistic theories of political decision-making cannot wipe clean too much of that complexity.

A study of how, and "who", actually makes decisions on vital issues in large metropolitan areas. Based on Chicago, and full case histories. Many patterns of influence are surprising, contrary to myths, and non-obvious. Most of the outcomes are contrary to the perceived "public interest".