The fastest revolving door you will ever get stuck in.
Pros
Good clients. Some of the work is interesting. Many good and talented people; great colleagues. Reasonably diverse skills among staff. Good opportunity for growth if you are young and inexperienced, as you will put in a lot of hours.
Cons
Corporate structure benefits the management and gives meager benefits to employees. Office managers get the credit for work well done, not those actually accomplishing the work. Work load is often heavy with little to no support; more experienced staff are expected to do their own production and put in whatever time is necessary in order to accomplish that. Sparse feedback for accomplishments and for hard work; criticism for making mistakes (due to not having adequate support) is more common. Extremely high rate of turn-over. Many of the projects look the same when finished. Voiced concerns to management are not taken seriously, as the attitude is that there are always other people willing to take the job if you don't want it. Only "designers" design; the architects are considered support staff and labeled as "technical."