Private military companies (PMCs) hit the headlines when the murder of four Blackwater employees in Fallujah in late March, 2004, prompted a U.S. attack on that city. By then, PMC employees in Iraq numbered in the tens of thousands. This large legitimate (in the sense of officially condoned) market for private military force was not anticipated in international law. The classic approach toward private military force was concerned with the rogue buccaneer and the rear-guard actions of colonialists trying to buck the tides of history. Adding to the current dilemma is vagueness about who is a combatant. There are no real front lines in wars where truck drivers and cooks are armed because they are targets of attack. This superb book addresses these important developments from an academic perspective, and brings together the best scholars concerned with this debate.

From Mercenaries to Market takes on two main tasks. The first is to provide a critical examination of what PMCs actually are. The second is to explain how international law deals, and how it should deal, with this shift. Penned by the world's most noted experts on PMCs, the chapters are free of the polemics that crowd many debates. One finds superb chapters by authors who have been critical of PMCs and their conduct and those who see in PMCs useful new ways of dealing with old problems. In bringing these and other viewpoints and analyses together, this book sets a standard for the study of this subject.

The first set of chapters lay out key features of the contemporary PMC market. Sarah Percy focuses on the challenge that PMCs represent to the politics of citizen armies. Old-fashioned armies in democracies need public support to work well. PMCs do not come with such entanglements. Indeed, PMCs offer some officials the attraction of fighting wars without significant public debate. Kevin O'Brien's counterpoint focuses on the benefits of flexibility and speed in deployment that private firms offer. How many more lives would have been saved if PMCs had stepped in to stop the genocide in Rwanda, or to save Sierra Leoneans or Liberians from predatory rebels while others occupied themselves in UN talkfests?

Anna Leander's chapter explains that the real issue is the private character of PMCs. As private actors, they can lobby officials. This reverses an old relationship in democratic countries where, in the ideal at least, militaries take orders from their civilian bosses. David Isenberg points to the tensions between officials who like to use PMCs because they are flexible and readily deployed, and those to whom flexibility is a code word for freedom from popular scrutiny and the slow and burdensome processes of public debate. Angela McIntyre and Taya Weiss note how governments and civilians facing the terrible ravages of war, especially where rebel groups break down into marauding gangs, might see PMCs as a godsend. But shifts in domestic politics occur here, too, as PMC success in providing protection usually brings a nasty reaction from the country's sidelined military and wrecks already awful civil–military relations.

By now it should be apparent that accountability is a core theme for this book and guides the concerns about the capacities and evolution of international law on private markets for military force. Louise Doswald-Beck points out, for instance, that rules on prisoner-of-war status evolved with states in mind. How should one regard captured PMC employees? Answering this question requires defining to whom PMC employees are ultimately accountable. Clarifying this matter might benefit some PMC employees. If states are liable, PMC employees are entitled to more protection under international law. Chia Lehnardt offers a pragmatic argument that state tasks have changed over time—all sorts of tasks get privatized these days—but this does not release state officials from liability for the behavior of their private agents.

PMCs have customers and have to compete against other firms to offer their services, notes Deboarh Avant. This relationship privileges performance in terms of helping to win wars. As recent incidents in Iraq involving PMCs show, there can be an undue focus on “getting the job done” to impress the client and get the next contract. Moreover, the market relationship changes who wins and loses in the decision-making process. Rich people generally are better at lobbying, and poor people are more likely to be heard in processes that involve public commentary and debate. To the extent that PMCs allow officials to make quick decisions, “the industry” wins, while citizens are left to pick up the tab and pay for the consequences. James Cockayne explains that officials can then distance themselves from blame for bad behavior among some PMCs while still benefiting from their capacities to do nasty things, like interrogate prisoners. Maybe some recent problems are a small price (in the eyes of some officials) for the flexibility that PMCs offer in the post–9/11 world, which demands fast action and unorthodox methods.

Andrew Bearpark and Sabrina Schultz speak for the profession. (Bearpark is the director general of the British Association of Private Security Companies and Schultz is that organization's director of policy.) They note the importance of reputation for PMCs, or as they prefer, private security companies. They argue that no PMC wants to be associated with bad behavior. But what if officials hire a PMC expressly to circumvent or violate rules that others define as good behavior?

Taken together, these authors provide the valuable service of debating whether the inherent characteristics of privatized coercion are compatible with accountability to the public. This book is a must-read for anyone interested in the growing presence of a private market for military force in the contemporary world, whether from a policy perspective or that of a more purely academic background. The editors chose their contributors wisely and accomplished the rare feat for an edited volume of fitting the chapters into a coherent whole. The high cover price is unfortunate, however. One would think that the demand in military academies alone would justify a lower-cost soft-cover edition.