Pros
Top company within the field, many diverse and large projects to work on, global opportunities within the company, coworkers are pretty friendly and relaxed, business casual environment.
Cons
AECOM is a company of acquisitions. Within the past 2.5 years that I've worked here, AECOM has acquired at least 8-10 smaller firms. This can have its pros and cons. The pro is it gives AECOM more opportunities to seek diverse projects. The con is you are adding more employees to the staff and thus possibly limiting growth opportunites for the current staff. Also staff must be at an associate level or higher before they can qualify for company bonuses. In order to become an associate you must work here for a minimum of 5 years before even being considered to become one.