Of the some sixty thousand vacant properties in Philadelphia, half of them are abandoned row houses. Taken as a whole, these derelict homes symbolize the city’s plight in the wake of industrial decline. But a closer look reveals a remarkable new phenomenon—street-level entrepreneurs repurposing hundreds of these empty houses as facilities for recovering addicts and alcoholics. How It Works is a compelling study of this recovery house movement and its place in the new urban order wrought by welfare reform.

To find out what life is like in these recovery houses, Robert P. Fairbanks II goes inside one particular home in the Kensington neighborhood. Operating without a license and unregulated by any government office, the recovery house provides food, shelter, company, and a bracing self-help philosophy to addicts in an area saturated with drugs and devastated by poverty. From this starkly vivid close-up, Fairbanks widens his lens to reveal the intricate relationships the recovery houses have forged with public welfare, the formal drug treatment sector, criminal justice institutions, and the local government.

The study of group actions is more than a hundred years old but remains to this day a vibrant and widely studied topic in a variety of mathematic fields. A central development in the last fifty years is the phenomenon of rigidity, whereby one can classify actions of certain groups, such as lattices in semi-simple Lie groups. This provides a way to classify all possible symmetries of important spaces and all spaces admitting given symmetries. Paradigmatic results can be found in the seminal work of George Mostow, Gergory Margulis, and Robert J. Zimmer, among others.

The papers in Geometry, Rigidity, and Group Actions explore the role of group actions and rigidity in several areas of mathematics, including ergodic theory, dynamics, geometry, topology, and the algebraic properties of representation varieties. In some cases, the dynamics of the possible group actions are the principal focus of inquiry. In other cases, the dynamics of group actions are a tool for proving theorems about algebra, geometry, or topology. This volume contains surveys of some of the main directions in the field, as well as research articles on topics of current interest.

Every night, somewhere in the world, three or four musicians will climb on stage together. Whether the gig is at a jazz club, a bar, or a bar mitzvah, the performance never begins with a note, but with a question. The trumpet player might turn to the bassist and ask, “Do you know ‘Body and Soul’?”—and from there the subtle craft of playing the jazz repertoire is tested in front of a live audience. These ordinary musicians may never have played together—they may never have met—so how do they smoothly put on a show without getting booed offstage.

In “Do You Know . . . ?” Robert R. Faulkner and Howard S. Becker—both jazz musicians with decades of experience performing—present the view from the bandstand, revealing the array of skills necessary for working musicians to do their jobs. While learning songs from sheet music or by ear helps, the jobbing musician’s lexicon is dauntingly massive: hundreds of thousands of tunes from jazz classics and pop standards to more exotic fare. Since it is impossible for anyone to memorize all of these songs, Faulkner and Becker show that musicians collectively negotiate and improvise their way to a successful performance. Players must explore each others’ areas of expertise, develop an ability to fake their way through unfamiliar territory, and respond to the unpredictable demands of their audience—whether an unexpected gang of polka fanatics or a tipsy father of the bride with an obscure favorite song.

“Do You Know . . . ?” dishes out entertaining stories and sharp insights drawn from the authors’ own experiences and observations as well as interviews with a range of musicians. Faulkner and Becker’s vivid, detailed portrait of the musician at work holds valuable lessons for anyone who has to think on the spot or under a spotlight.

Opera and musical theater dominated French culture in the 1800s, and the influential stage music that emerged from this period helped make Paris, as Walter Benjamin put it, the “capital of the nineteenth century.” The fullest account available of this artistic ferment and its international impact, Music, Theater, and Cultural Transfer explores the diverse institutions that shaped Parisian music and extended its influence across Europe, the Americas, and Australia.

The contributors to this volume, who work in fields ranging from literature to theater to musicology, focus on the city’s musical theater scene as a whole rather than on individual theaters or repertories. Their broad range enables their collective examination of the ways in which all aspects of performance and reception were affected by the transfer of works, performers, and management models from one environment to another. By focusing on this interplay between institutions and individuals, the authors illuminate the tension between institutional conventions and artistic creation during the heady period when Parisian stage music reached its zenith.