Pros
Amazing and thoughtful designers come and go from the firm, so you will meet many great people and develop life-long connections. You will meet people who care about quality design, best practices and professional mentoring, despite the corporate culture. PTO is generous and the view of the lake is amazing. No dress code. Big company, so attention from building material reps is often good and responsive. Once you figure out how to navigate the system, it's a breeze to sit back and be comfortable.
Cons
Arcadis owns RTKL and with the latest merger with Callison, they've brought in a heavier hand on operations. Slowly but surely, CallisonRTKL is losing their autonomy as a design firm and will be fully consumed into the mega-corporation of Arcadis. Arcadis only cares about profit and ignores the triple bottom line. Leadership is often uninspiring and middle management is light and burned out from lack of support. Most clients are not really interested in quality buildings, mainly just cheap and fast which has lead to many problems in construction and beyond. Production work is currently being forced overseas by Arcadis to save money, but it causes new communication stresses on the current workforce and if successful, threatens the traditional legacy of learning technical architecture through drafting and face-to-face mentoring experience and construction administration. If you are a designer who thinks they can change the world here, you might have some small victories, but 'safe' design is the typical mode. Innovation is not really possible in the current bureaucratic work environment where adversity to overhead starves growth and freedom for employees.