Higher Ed Admin
Pretty standard 40 hour week. I'm in my office / on campus basically from 8-5 all week. I almost always take a full hour (or a bit more) for lunch - I like to go for a short swim as part of it. And I do a lot of non-work stuff at my desk - plan vacations, read articles, investment / purchase research, schedule appointments, etc.
Many of my peers work MANY more hours than that (60-70+), between work dinners, weekend events, travel, 24/7 phone & email, etc. I've always been firm in my work life balance, though, and I haven't had trouble getting promotions. At the same time, though, I don't think I could go any higher without sacrificing my work life balance (hence I don't apply for those jobs).