Great culture and encouraged to follow your interests where possible. Greater ownership of own work, and fairly egalitarian approach to collaboration.
With what I've seen so far, I could genuinely see myself making a career within AtkinsRéalis with very little reason to move elsewhere.
Cons
Will require significantly higher personal organisation than other companies from what I understand. Can have peaks and troughs as far as quality of work sent your way is concerned. This is to be expected in a consultancy, but it may not be for you if you only want to focus on a single aspect.
The pay is good, generally a good culture. Really great work life balance and Flexi working.
Cons
Becoming very corporate.
Some politics as is usual with these large organisations.
Grad scheme was not the best experience - kept on same project for entire scheme