Abstract: Reusability of deployment plans and dependencies thereof. A method defines contracts as between multiple deployment plans, the contracts representing dependencies between them; defines wait task(s) in a first set of the deployment plans, a wait task being associated with a contract and completion of the wait task and progression of a deployment plan in which the wait task is defined being dependent on satisfaction of the contract; defines signal task(s) in a second set of the deployment plans, satisfaction of the contract being based on status of signal task(s); selects a collection of deployment plans for concurrent execution, at least one contract of the contracts representing at least one dependency between the collection; and manages the concurrent execution of the collection. Managing controls progression of the execution by enforcing the at least one contract, which enforces the at least one dependency between the collection in the execution of the collection.