Pros
A collegial and respectful culture inside most individual imprints and departments; smart, conscientious, fun, and largely un-snobby employees; since there aren't really enough people to get the work done initiative is always welcome so there are ways to learn & grow on the job (though you may never be paid for it or officially promoted); Perseus imprints and distribution clients publish lots of wonderful good books to be proud of. Lots of opportunities to socialize with bright, fun colleagues. Most people are politically progressive & engaged in issues/causes/endeavors beyond their career ambitions.
Cons
In the last few years management has been focussed on selling the company, cutting overhead, and/or growing the distribution side of the business, and has devoted few resources devoted to building Perseus publishing imprints, better and more integrated systems, or supporting chronically overworked and underpaid staff. Everyone has more to do than any one person can possibly do, and there is too little support staff for the volume of work, ever more stringent budgets, and a mishmash of primitive systems to navigate that makes every task take longer. Since the near- but aborted sale of the company to Hachette and Ingram, morale is low and anxiety high. Raises are typically 1-2% if you get one at all, less than the rise in benefits cost and cost of living, and management's attitude about that is that if you don't like it, go get another job --we'll easily replace you with someone else who won't complain. Unsurprisingly, many employees feel unseen, unheard, burned out, and devalued. It didn't used to be like this at Perseus. Five+ years ago the company and its culture seemed optimistic, open, creative, collegial, nonhierarchical and innovative, and employees were devoted to it despite a somewhat lower pay scale than the majors. That's changed, and it's sad.