“ Since 1935, the recipe book for building roads in the US has been a document called the Manual on Uniform Traffic Control Devices. Little known outside of transportation circles, the MUTCD has a big impact on public space: It lays down the law on street markings and design, standardizing signage and making driving as seamless as possible, so that motorists in New York City, Chicago or Los Angeles are all familiar with the same set of signs and road markings.
Shades of ossification from the epilogue of the Knowledge > Evolution section of the manual:
“ Epilogue
Will the MUTCD ever be “done”?
“What’s past is prologue.” Just as the world changes, so, too, does the MUTCD along with it. Maturing and developing technologies and changing trends—in travel patterns, people’s preferences and priorities—mean that there is always room for improvement in the MUTCD to respond to a changing environment. In this regard, the MUTCD is never really “done.” It is a document that evolves with the times.
Although not a “live” document in which changes are made at will, the MUTCD is a living document with an established, open process that offers the public the opportunity to weigh in on contemplated changes before they are adopted, and allows agencies time to adopt and implement changes in a systematic, manageable way that causes the least disruption to the traveling public. And with its established processes for evaluating new concepts, the ability to issue official interpretations of its provisions, and advance proven concepts through interim approvals, the MUTCD continues to be responsive to traveler needs even between new editions.”