Pros
The office quarterlies, department quarterlies, holiday parties, and rendezvous. Not to mention all of the after-work happy hours, clubs, and social events. This is a very social company so make sure you're very extroverted. Everyone is a team player and supportive of each other so when a problem arises there are people lined up to help.
Cons
The projects you will encounter are not challenging unless they place you as team lead at a client, in which case navigating political waters and project management should be your strengths. It is expected of the consultant to grow their skill sets outside of the client work environment which is very difficult since 40% of one's bonus is based on extra curricular activities within Slalom. They also advertise an "unlimited" training budget, but that is very subjective.