The violent actions of a few extremists can alter the course of history, yet there persists a yawning gap between the potential impact of these individuals and what we understand about them. In Engineers of Jihad, Diego Gambetta and Steffen Hertog uncover two unexpected facts, which they imaginatively leverage to narrow that gap: they find that a disproportionate share of Islamist radicals come from an engineering background, and that Islamist and right-wing extremism have more in common than either does with left-wing extremism, in which engineers are absent while social scientists and humanities students are prominent. Searching for an explanation, they tackle four general questions about extremism: Under which socioeconomic conditions do people join extremist groups? Does the profile of extremists reflect how they self-select into extremism or how groups recruit them? Does ideology matter in sorting who joins which group? Lastly, is there a mindset susceptible to certain types of extremism? Using rigorous methods and several new datasets, they explain the link between educational discipline and type of radicalism by looking at two key factors: the social mobility (or lack thereof) for engineers in the Muslim world, and a particular mindset seeking order and hierarchy that is found more frequently among engineers. Engineers' presence in some extremist groups and not others, the authors argue, is a proxy for individual traits that may account for the much larger question of selective recruitment to radical activism. Opening up markedly new perspectives on the motivations of political violence, Engineers of Jihad yields unexpected answers about the nature and emergence of extremism.

This Element argues that the low dynamism of low- to mid-income Arab economies is explained with a set of inter-connected factors constituting a 'segmented market economy'. These include an over-committed and interventionist state with limited fiscal and institutional resources; deep insider-outsider divides among firms and workers that result from and reinforce wide-ranging state intervention; and an equilibrium of low skills and low productivity that results from and reinforces insider-outsider divides. These mutually reinforcing features undermine encompassing cooperation between state, business and labor. While some of these features are generic to developing countries, others are regionally specific, including the relative importance and historical ambition of the state in the economy and, closely related, the relative size and rigidity of the insider coalitions created through government intervention. Insiders and outsiders exist everywhere, but the divisions are particularly stark, immovable and consequential in the Arab world.

In Princes, Brokers, and Bureaucrats, the most thorough treatment of the political economy of Saudi Arabia to date, Steffen Hertog uncovers an untold history of how the elite rivalries and whims of half a century ago have shaped today's Saudi state and are reflected in its policies. Starting in the late 1990s, Saudi Arabia embarked on an ambitious reform campaign to remedy its long-term economic stagnation.

The results have been puzzling for both area specialists and political economists: Saudi institutions have not failed across the board, as theorists of the "rentier state" would predict, nor have they achieved the all-encompassing modernization the regime has touted. Instead, the kingdom has witnessed a bewildering melange of thorough failures and surprising successes. Hertog argues that it is traits peculiar to the Saudi state that make sense of its uneven capacities.

Oil rents since World War II have shaped Saudi state institutions in ways that are far from uniform. Oil money has given regime elites unusual leeway for various institutional experiments in different parts of the state: in some cases creating massive rent-seeking networks deeply interwoven with local society; in others large but passive bureaucracies; in yet others insulated islands of remarkable efficiency. This process has fragmented the Saudi state into an uncoordinated set of vertically divided fiefdoms.

Case studies of foreign investment reform, labor market nationalization and WTO accession reveal how this oil-funded apparatus enables swift and successful policy-making in some policy areas, but produces coordination and regulation failures in others."

Although most Arab countries remain authoritarian, many have undergone a restructuring of state-society relations in which lower- and middle-class interest groups have lost ground while big business has benefited in terms of its integration into policy-making and the opening of economic sectors that used to be state-dominated. Arab businesses have also started taking on aspects of public ser- vice provision in health, media and education that used to be the domain of the state; they have also become increasingly active in philanthropy. The 'Arab Spring,' which is likely to lead to a more pluralistic political order, makes it all the more important to understand business interests in the Middle East, a segment of society that on the one hand has often been close to the ancien regime, but on the other will play a pivotal role in a future social contract. Among the topics addressed by the authors are the role of business in recent regime change; the political outlook of businessmen; the consequences of economic liberalisation on the composition of business elites in the Middle East; the role of the private sec- tor in orienting government policies; lobbying of government by business interests and the mechanisms by which governments seek to keep businesses dependent on them.

In Princes, Brokers, and Bureaucrats, the most thorough treatment of the political economy of Saudi Arabia to date, Steffen Hertog uncovers an untold history of how the elite rivalries and whims of half a century ago have shaped today's Saudi state and are reflected in its policies. Starting in the late 1990s, Saudi Arabia embarked on an ambitious reform campaign to remedy its long-term economic stagnation.

The results have been puzzling for both area specialists and political economists: Saudi institutions have not failed across the board, as theorists of the "rentier state" would predict, nor have they achieved the all-encompassing modernization the regime has touted. Instead, the kingdom has witnessed a bewildering melange of thorough failures and surprising successes. Hertog argues that it is traits peculiar to the Saudi state that make sense of its uneven capacities.

Oil rents since World War II have shaped Saudi state institutions in ways that are far from uniform. Oil money has given regime elites unusual leeway for various institutional experiments in different parts of the state: in some cases creating massive rent-seeking networks deeply interwoven with local society; in others large but passive bureaucracies; in yet others insulated islands of remarkable efficiency. This process has fragmented the Saudi state into an uncoordinated set of vertically divided fiefdoms.

Case studies of foreign investment reform, labor market nationalization and WTO accession reveal how this oil-funded apparatus enables swift and successful policy-making in some policy areas, but produces coordination and regulation failures in others."