Pros
Your career and work experience is very different depending on your manager. If you get a good one, you'll be happy here. If you don't it sucks and people quit. Benefits are very good, health, dental, life insurance, etc. You also can get free access to the fitness center which is nice. The company has a great mission, but I don't know that people outside of HMSA get it or support it. We're non-profit so it's not like we are super well paid...
Cons
A lot of managers are working managers, which means that they don't have the time or energy to devote to actively working with their subordinates to help them progress. Career development is difficult. There are policies in place that discourage you from applying to other jobs (you have to ask your supervisor before applying or i've heard you could get fired). You can only apply for one at a time. But information about the different areas of the company is hard to find, so you don't really know what you might want to apply for. Sometimes your supervisor pushes you into a job that you don't really want, and people who have this happen to them aren't very good at the jobs they get. There's no training on things. You're handed a computer and just expected to work, but sometimes you don't even know how to log on. There are all these unwritten rules that don't get explained. The company encourages you to use the stairs and then locks them without really telling you. Management doesn't explain why they are doing things, so stuff doesn't always make sense. We start and end projects/efforts without real reason. We tried to go AGILE but I don't know what happened to it, and I think it might be cancelled, even though we must have spent a lot of money on consultants. HMSA loves consultants. I don't get why they don't just train us to do the work of consultants and save money. There's a lot of people who have quit to work for other companies so a lot of departments are short-staffed, and work doesn't get done.