Pros
Established, financially secure company with favorable industry recognition. Benefits and pay are above average. Projects are interesting, challenging, and occasionally include landmark facilities such as stadiums, universities, civic structures etc. Very structured operations (if that is your thing). Geographically diverse (if your willing to relocate for career advancement opportunities). Some very well respected construction professionals, both locally and in corporation operations.
Cons
One thing that differentiated my tenure at Mortenson from my current employer is that there seemed to be a highly competitive (at times cut-throat) atmosphere that tended to breed a lot of "people drama" and unneeded stress. Couple this with a management philosophy that fosters "high level thinkers" and you start to see signs of dysfunction with an imbalance between "strategists/thinkers" and "doers". If you are like most people and find reward in hard (tangible) work and being in integral part of a team, expect to encounter some frustration. There is also an unusually high level of management oversight and controls. This could be viewed as a good thing in the fact that management is highly involved in all levels of decision making (thus individual accountability is limited), but can be frustrating if you like autonomy or are looking for rapid career advancement, or just need to get something out the door to a client. Trying to procure the simplest items for day to day operations involves an extremely involved corporate process. Controls/software/hardware was antiquated, but improvements were coming. Soft perks cycled with margins, but compared to my current employer, were somewhat limited.