Pros
The culture is such that finding the right person is always just a couple phone calls away. Almost everyone goes out of their way to help coworkers from across the company. And, being such a large company, there are many positions likely to suit most anyone, so if you have a desire for a change and the will to work through the company to make a move (networking, expressing your desires, working hard and taking on new challenges), it is possible to move into something great.
Cons
It can be a competitive environment because, as with any company but particularly those not growing at unsustainable rates, there are limited rewards (pay increases, bonuses, leadership positions). The company has very good compensation compared to market values, but people want more relative to their peers, and not everyone can be above average, by definition. There is a lot of focus on annual performance reviews in the culture that can drive non-collaborative behavior in areas where leaders aren't valuing collaboration, or publicly emphasizing valuing collaboration, as much as they should. Dow also hires top-notch people, so there is disappointment when many who have been told they are the best through their life end up being told they are average here.