This sprawling book by a Pakistani diplomat and anthropologist examines why relations between Muslims and non-Muslims in Europe are so contentious—and what might be done about it. The author and his research team spent four years interviewing Muslims in Europe, including many religious and community leaders. Their troubling, if unsurprising, finding: Muslims feel disadvantaged, stereotyped, and marginalized. Sadly, the book has little to say about the roots of these perceptions. Ahmed seems more interested in his policy prescription: to override Muslim extremists and white nationalists alike in favor of a more tolerant and pluralistic European culture. That is a laudable goal, but Ahmed’s vague proposal—to reform modern Europe along the lines of medieval Muslim Spain—seems far-fetched and inappropriate, not least because medieval tolerance was a strategy designed to accommodate a popular majority. Even if Ahmed’s project were feasible and desirable, the rest of his vision is too hazy to resolve the everyday disputes that would still arise over how people dress, whom they marry, and what political ideals they favor.