Pros
Very smart employees- most people have PhDs. Interesting projects that change frequently. On the cutting edge of applicable science and engineering. Pays relatively well.
Cons
Sometimes you will be working for the evil do-ers and trying to make it seem like they did nothing wrong. You have to keep track of every single hour you work. Its tedious and annoying and doesn't leave much room for professional growth, since this isn't "billable". Vertical structure, there is only one way to up! There is no changing divisions to get different kinds of experiences or move up. This means there is lots of competition among coworkers but at the same time you need to "market" to coworkers to get put on their projects, so this creates a very weird dynamic. How one develops themself in this company is a total mystery. You need to get more clients to be promoted but no one teaches you how to do that and everyone is very protective of their clients and contacts because that is their bread and butter. Too many people who have been in the company at the same position for 10+ years. Its not inspiring.