Pros
Good work-life balance, it is not a sweat-shop like some other engineering companies. Good benefits. Good for new graduates as the company does not care much about competency or experience: new graduates can get an opportunity to advance very early in their career without any competence, knowledge and experience.
Cons
Unfair internal politics, incompetent clueless managers will dictate your life, from the project you are given to the supervisor/manager you are given (and some of them are very mean). Nothing is based on the actual competency of staff, just politics and appearances. Hard work, experience and/or competency are never rewarded. (The only reward is bullying) If their incompetent managers fail to find work, Atkins will just get rid of staff, not the managers who failed to do their job. Also the management is only interested in their own career progress and make sure they are rewarded/ promoted, they will never lift a finger to help you and/or look after you. One example of their management: when my manager asked me to do p'way design, I explained that it is another branch of engineering and it's not what we do. The manager then informed directors that I refused to do work and cooperate and I was removed from the project. Just because the manager did not know what p'way is!