The uneven outcome of a reportedly frustrating conference, most of the conference papers in this volume are dated, generally uninspired and have a huge blind spot regarding race.
The survey article by Sean Wilentz regarding the development of the US working class is useful for thinking about the topic (...and is loaded with references on the same); the contributions by Alan Dawley & Micheal Reich are interesting.
The closing essay from Alice Kessler-Harris starts out as a broad review of the conference for which the essays collected were prepared, but turns into a powerful (...if at times essentialist) call to center gender analysis in labor history.
Spoiler Alert: the conference didn't figure out how to synthesize approaches to labor history--but it's participants didn't interrogate the possibility of doing so either...