Antitrust laws play a prominent role in the business environment of many nations. Indeed, if one is a regular reader of the New York Times or Wall Street Journal, the chances are good of seeing in any given week at least one, and often several, articles devoted to some aspect of antitrust...

In this chapter, we begin our discussion of antitrust economics by considering what many consider its most central element: its ban on "price fixing" - that is, agreements among competitors over the prices they will charge or the outputs they will produce. Indeed, the prohibition on price fixing...

In this chapter our attention turns to horizontal merger policy. The Sherman Act's prohibition on "contracts, combinations, and conspiracies in restraint of trade," whose application to price fixing we discussed in Chapter 2, also applies to horizontal mergers, but with an important difference:...

We analyze the optimal dynamic policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and occur over time. Approving a currently proposed merger will affect the profitability and welfare effects of potential future mergers, the characteristics of which...

Recently there has been a notable increase in interest in antitrust law in much of the world. This chapter discusses antitrust policy toward horizontal mergers, the area of antitrust that has seen some of the most dramatic improvements in both economic tools and the application of economics in...

We study optimal merger policy in a dynamic model in which the presence of scale economies implies that firms can reduce costs through either internal investment in building capital or through mergers. The model, which we solve computationally, allows firms to invest or propose mergers according...

We analyze the optimal policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and firms choose which of several mutually exclusive mergers to propose. The optimal policy of an antitrust authority that seeks to maximize expected consumer surplus involves...