Pros
The people are awesome and very talented. Flexible working conditions and good work life balance (in some teams, not all).
Cons
It's a big company so you can sometimes get forgotten. I had someone in my team literally taking multiple days off "working from home" and doing half days without the management noticing they were rorting the system. This may be a pro if you are a lazy person but personally I like to work hard and feel like I did a good job - not slack off and get away with it. Promised a lot in the graduate program, then cancelled planned trips due to budget cuts and cut the overall program short. Very disappointed. My management were useless. Wasted company money and favoured certain team members they were friends with over those working hard and keeping the team afloat with projects. Then when redundancies came they got rid of the hard workers and kept their idiot mates. That's when I left. I suspect further redundancies in 2019 - I certainly would have let them go if I was an executive. You can't lose the company hundreds of thousands of dollars and get away with it forever. You can't get a decent pay rise unless you threaten to leave. This is well known across AECOM Australia.