Pros
Having the name Booz Allen Hamilton on your resume impresses recruiters. There are probably good teams at Booz Allen but I've never encountered any.
Cons
Booz Allen operates on a team structure where the Senior Associates dictate the culture of their domain. Of the four teams I was on, one Senior didn't care about the people under him, another only cared about how you contributed to proposals (not how well you supported the client), a third created a toxic work environment and flat out told me he would not help me find another contract after I said I was looking for another one, and the last one was dishonest and met with government officials to get insider information on upcoming contract information. Working our way down the management structure to the Lead Associates, the story doesn't get any better. On one team, the Lead was friends with certain people outside of work. Those people were looked after and got the promotions and bonuses. For everyone else, it's not hard to fabricate some excuse as to why you didn't get the promotion or didn't qualify for a bonus. Being the one in charge of performance metrics, I knew who really deserved the promotions and bonuses. When the Lead's friends who are in the bottom 50% get promoted twice in 2 years and others get nothing, its clearly favoritism. Other Leads stake their career on the work of those under them because they don't have the skill to get the work done. They will act friendly to you but if you ever ask for anything in return like a raise, you wont get any help. And once you move on, they will turn against you. Moving down to Associates, you encounter a group of people who throw around their position as a low level manager to cover for the fact that they probably don't know how to do any of the work they're asking you to do for them. And once you do that work, they generally have no moral qualms with taking all the credit. And now we get to the backbone of Booz Allen, the Consultants and Senior Consultants. These are the people who do the real work at Booz Allen and generally don't get paid any near the market average to do so. In this group there are two types of people, those who are enamored by the Booz Allen name and will try to move up the ladder and those who realize that they're getting paid well below the market average and move on to something better. Unfortunately, the former group often coincides with less talented people who like to play it safe and just sit there and do their menial job and nothing more. Beyond the employees, Booz Allen has corrupted the government to such an extent that they should be banned from competing on contracts at many agencies. After moving on from Booz Allen, I joined a small company that had recently unseated Booz Allen from a contract after the office consolidated two teams (Booz Allen's and ours) into one team. The company I joined was given high ratings while Booz was given average ratings. We were given a 6 month contract with the option of additional 6 month increments. We were also competing with Booz Allen for another contract in the same office. Booz Allen, still unhappy being unseated and having already corrupted the government official in charge of the contracts, had the government add an addendum to the contract we were both competing for that said the winner would get both that contract and the contract that Booz had just lost (the one they were rated as average). Booz won the contract and we were out despite having fairly won the contract 6 months prior and having had years of excellent performance in that position. After winning, Booz Allen tried to recruit everyone from the team I was on. Not a single person went to Booz.