The MUTCD is the authorized national guide in all facets of using TCDs (traffic control devices), but state transportation agencies differ in how they comply with MUTCD standards. For example, some states adopt the MUTCD as their standard. Other states adopt the national MUTCD along with a state supplement that might prescribe which of several allowable options are selected for the state's specific purposes. Still other states use the national MUTCD as the basis for developing their own State Traffic Control Device manuals, which must be in substantial conformance to the national MUTCD. More... 

National MUTCD

MUTCD's & Traffic Control Devices Information by State

Status of the MUTCD (2003 Edition)