Media buying
Media buying is the execution and commercial management of the plan: negotiating, purchasing and stewarding the inventory the plan calls for, whether through platform auctions, programmatic deals or direct publisher agreements. Planning decides the allocation; buying secures and delivers it.
In practice
In digital self-serve platforms, planning and buying blur into one workflow. In offline and premium direct media, buying remains a distinct discipline of negotiation, orders and delivery management.
The planning-buying handover is a classic failure point - which is why activation from a single source-of-truth plan matters.