Sign supports and their foundations are designed and constructed to hold sign panels rigidly in the proper position. Supports should resist swaying and failure due to wind or displacement by pedestrians or vandals. When hit by a vehicle, a support should break away as designed so that it does not pose a safety hazard to motorists.

The type of support depends primarily on the size of the sign. A variety of shapes and sizes of support material are used.

Chapter 4 provides more information on maintenance of roadside sign supports.