Discussions about academic publication (for example, the recent Elsevier boycott, the actual cost of publication, open-access initiatives by universities and funding agencies, citation cartels, or post-publication review) are often muddled by the fact that publication practices and culture vary significantly from one discipline to the next. I would like to see some of these differences explicitly teased apart.
I'm particularly interested in exactly how publishers in different disciplines help move authors' ideas to formally published papers. Publishing in any discipline requires the combined effort of authors, publishers, editors, and reviewers, but the distribution of these efforts (and their associated costs) seems to vary from one discipline to the next.
What specific services do publishers provide to authors in your discipline? Please only one answer per discipline. (If necessary, define "discipline" as "set of researchers with the same publication practices".)
(At a deeper level, I am curious why so many people seem to associate the value, authority, and prestige of various publication venues with their publishers instead of their authors, editors, and readers. But that's not a good question for StackExchange; let's stick to the narrower factual question.)
I'll provide an answer for my own discipline.