Pros
Market recognition as a premiere provider of services; sense of accomplishment in assisting great professionals with career opportunities; overall (most offices) sense of teamwork and belonging to a great organization; awesome training culture and tool/resorces provided; great place for recent grads to learn business skills and interact with C-Level, hiring managers and directors that they may not have been able to receive at other employers.
Cons
Parity in promotions; local leadership not truly in-line with corporate directives (not following the same directives and policies they are instructing you to do so); "face time" required to be considered a team-player, rather than your body of work and results speak for itself; typically instructed to price RFP's and prospective client(s)/projects too high thus limiting market growth as they want to set a "target spread" or margin for each professional placed on-site/project - this leads to competitors gaining marketshare based on cost alone rather than quality of candidates.