Run rig, or runrig, also known as rig-a-rendal, was a system of land tenure practiced in Scotland, particularly in the Highlands and islands. The land was divided into touns or townships, comprising an area of cultivable "in-bye" land and a larger area of pasture and rough grazing. The in-bye was divided into strips - "rigs" - which were periodically reassigned among the tenants of the township so that no individual had continuous use of the best land. From the mid-18th century the system was steadily supplanted in Scotland as the in-bye was divided into crofts under fixed tenancy, however run rig survived into the 20th century in some parts of the Hebrides.
In Ireland, a similar system was called rundale. The run rig system of tenure should not be confused with the agricultural management practice known as ridge and furrow.