In my employment, we signed a basic contract, upon employment. Also, those goals and whatnot that are set in employee evaluations? They are contract milestones. At the company I worked for, HR was run by the General Counsel. Fun bunch.
Generally, the more "intellectual," or "knowledge-based" a job is, the more likely it is to have a well-established (and enforced) contract.
I am not bound to deliver anything at all as part of my employment agreement. There are no set deliverables. Maybe others have different experiences.