Vantaggi
It's a huge company doing project work in just about every sector, so opportunities to switch jobs are pretty good. As a current employee, they've really improved access to other jobs opportunities for current employees by creating an internal job search site that puts you in touch with the recruiter.
Svantaggi
Working hard to grow the company, but in some ways by nickel and diming the employees. Benefits have decreased twice in the past year. If you want a significant promotion or salary increase, you need to apply for a new position within the company. If you're on a project that either ends or is not won back, which happens a lot in project work, you can pretty much bank on being laid off. There's very little effort to help you find new work. Or if you're not 100% billable, don't trust that your job is secure. It's very common for employees to network internally to find enough work to remain billable and to secure their jobs. It can create a stressful work environment.