Pros
ERM is very people-centric and invests heavily in training. It conducts annual engagement surveys on which it achieves high scores compared to other companies. There is a clear (albeit not an easy) path to partnership for those associates wishing to put in the time and effort to be promoted. ERM has a substantial effort to fund and support environmental and sustainability causes, and tracks its carbon footprint so that it can set targets for reducing it. ERM attracts some of the most intelligent, highly accomplished people in the industry and affords its people the opportunity to work on challenging and interesting (sometimes even fun) projects. While it has over 140 offices in 41 countries there is a strong sense of community between locations. Employees are encouraged to work remotely and are provided the tools and resources they need to do so effectively.
Cons
Working as a consultant involves long hours and extensive travel and that life can be difficult for some. ERM's history of growth by acquisition has created some disgruntled legacy employees who can be difficult to get along with ("life was perfect before ERM bought out Joe's Consulting Shack). The lack of direction and feedback from leadership and frustrating because your boss may be located in another State or constantly on the road. As others have mentioned, billability is a primary concern and as consultants are typically overtime exempt employees, those who choose this life and expect extra compensation for working long hours are likely to be disappointed.