1. n. [Well Completions]

A single wellbore having tubulars and equipment that enable production from two or more reservoir zones. In most cases, at least two tubing strings will be used to provide the necessary level of control and safety for production fluids. However, in some simple dual completions, the second or upper zone is produced up the tubing-casing annulus. The wellhead and surface flow-control facilities required for multiple completions can be complex and costly; hence, multiple completions are relatively uncommon.