Note: the following content was written based on the 10th edition of the MUTCD. It will be updated soon to reflect the 11th edition of the MUTCD, which became the current edition in December 2023.
In the first three decades of the twentieth century, the wide variety of early traffic signs, signals, and markings created the need for uniformity and consistency. A number of efforts were undertaken in the 1920s towards this goal, including the 1925 Report of Joint Board on Interstate Highways, led by the American Association of State Highway Officials (AASHO). The report developed the US highway system and included recommendations for standard signs. Following this report, AASHO published a manual in 1927, which provided specifications for only rural signs. In 1930, the American Engineering Council published a manual for signs, markings and signals for urban areas. The problem of the two manuals led to the creation of the first MUTCD.
The first MUTCD was published in 1935 and there have been a total of ten editions to date. The first MUTCD was published to provide uniformity in the appearance and use of traffic control devices (TCDs). Later editions represent continuous improvement in MUTCD content.
1935
The ten MUTCD editions can be divided into four basic eras of development, as indicated below.
Initial Era
1935 and 1942
These two MUTCD editions represent the starting point for the MUTCD. Content is divided into application (selection), design, location/installation, and maintenance for each type of TCD.
Transition Era
1948 and 1961
These two editions represent the transition from the roadway network of the first half of the twentieth century to the Interstate period through the 1960s.
Mature Era
1971, 1978, and 1988
The three editions of this era are essentially continuous updates of a single edition. The 1971 MUTCD marked a significant change from the prior edition with the expansion of content and the introduction of many sign symbols. These manuals were revised numerous times.
Modern Era
2000, 2003, and 2009
The three editions of this era represent a significant change from prior editions. The size and content of the MUTCD was expanded and the format was modified to provide headings for the level of mandate (Standard, Guidance, Option, and Support).