Positive People, Positive Environment - Support Engineer Gorbel Employee Review

The headline I used is something the company highly stresses. However it has not been my experience during the past three years. There are a lot of employees that have worked for the company for 10-15+ years and it is very difficult to offer new ideas and processes. It's been my job to rebuild a specific process within a department and I actively receive push-back from other departments when trying to make improvement changes. My manager gives me the highest rating each year on my review as I am making the improvements he wants to see, but can't impliment much due to the push-back or sometimes refusal by other departments to work with me.