-Terrible place to work for young people. Even you if you have 5 years experience, expect to do data entry until you can work up the corporate ladder. Basically, you have to "do your time" no matter what your credentials. AECOM is not a meritocracy.
-Don't expect to be creative here. If you don't do work exactly by the 10 page checklist, you will receive push back, even if you have good ideas for improvement.
-Managers treat employees like a number. If you have 40 hours a week, expect to be left alone (sometimes I wondered if people realized I still worked there). As soon as you need more work or are not 100% billable, expect extreme micromanagement, aka "please send me what you worked on yesterday in 15min intervals." There is no middle ground.
-If you want a challenging job, look elsewhere. If you have a science or engineering degree and you want to float slowly to middle management over 10 years without creating anything or thinking outside of the box, work here.
-With that said, AECOM is actually a good place to be for a decent job with a decent salary and decent benefits with minimal effort. But you won't ever come to work excited.