An operations group tasked with accepting and supporting a software release. This group wants a predictable process, they view releases as incidents to be managed, and they answer to a business that wants predictability and accountability.
One or more development groups tasked with creating software to be released. These groups tend to be more diverse. You might have one development group that is using bleeding-edge technology to create a next-generation website that is more research than development, and another group developing applications against Oracle that is more predictable.