• D20 Standard for Traffic Records Systems

  • Note: ANSI accreditation of D20 has been removed, to allow D20 to be updated more frequently so it can reflect data definitions currently being used. For more details see the History tab.

    Purpose of D20

    As the use of computerized data systems for motor vehicle programs increases, the need to transfer data between those systems and organizations steadily increases. The D20 standard for Traffic Records Systems contains data element definitions used by the motor vehicle administration community. The standard provides standard terminology and coding instructions that promote uniformity of data elements exchanged between organizations in the following areas:

    • Motor vehicle registration and titling
    • Driver and commercial driver licensing
    • Motor vehicle inspection and insurance

    Advantages of Using D20

    Communication standards such as D20 allow organizations (such as jurisdictions) to have a standardized convention to exchange business data. Through this exchange, driver and registration information is available to assure the issuance of accurate licenses, registration, and titles.

    D20 is designed to facilitate continued coordination among data system developers. For new systems and system modifications, organizations are encouraged to use data elements in the D20 dictionary whenever possible to promote consistency and uniformity.


    AAMVA and Industry Usage

    D20 definitions are used in:

    • AAMVAnet systems to communicate between the jurisdictions and their partners. 
    • The encoding of data on DL and ID Cards 
    • The Model Impaired Driver Records Information System (MIDRIS) and other electronic systems outside AAMVA.
    • The National Information Exchange Model (NIEM) and other data standards.

    D20 Maintenance

    Terminology and codes used in the D20 dictionary come from many sources. Whenever possible definitions from other standards, practices and rules are used to maintain consistency. 

    Most requests to enhance D20 originate from Motor Vehicle Agency systems because the D20 data definitions are used in the exchange of data between these systems.

    However, D20 is an open standard, therefore any interested party may submit a request to update D20. Requests should be emailed to AAMVA Enterprise Architecture.

     The following document is the latest approved edition of D20:

    While the content of the dictionary has expanded and evolved since it was first published, its usage has not changed. 


    The need for the ANSI-D20 Data Element Dictionary for Traffic Records Systems was created by the Federal Highway Safety Act of 1966. This Act required states receiving federal highway safety funds to develop better systems for collecting and processing data for operating safety programs. "Traffic Records" refers to records related to:

    • Motor vehicle registration
    • Driver licensing
    • Highway design and operations
    • Accidents
    • Financial responsibility
    • Motor vehicle inspection
    • Commercial vehicle reciprocity
    • Traffic law enforcement
    • Emergency medical services


    Under the leadership of AAMVA, over 300 people from more than 80 public and private organizations participated in a D20 Parent Committee which compiled the dictionary. With funding and computer services provided by the National Highway Traffic Safety Administration (NHTSA) and Federal Highway Administration (FHWA), the first edition of the dictionary was issued in 1979 as the American National Standard ANSI D20-1979.


    In the 1980s, the D20 Parent Committee dissolved. The responsibility for the maintenance of the D20 dictionary was transferred to AAMVA’s Standing Committee on Motor Vehicle Information Systems (MVIS) after a 1984 ballot of the D20 Parent Committee. On May 6, 1986, MVIS formally submitted a request to the American National Standards Institute (ANSI) that AAMVA be accredited as the sponsor charged with maintenance of the D20 Dictionary. ANSI notified AAMVA on August 28, 1986 that the request was approved.


    On October 11, 1993, a second edition of D20 was approved by ANSI as the ANSI Data Element Dictionary for Traffic Records Systems D20-1993. In the second edition, many data elements were updated for greater compatibility with current operating data systems.

    In 1998, the third edition of the standard was published as the Data Element Dictionary for Traffic Records Systems, ANSI D20-1998. In the third edition, the Dictionary is synchronized with the AAMVA data repository. The AAMVA repository was developed using the AAMVA Electronic Data Interchange applications (used by the AAMVAnet community nationwide) as a source of reference. These applications encompass the driver licensing, vehicle registration and titling, and motor carrier registration business areas of the departments of motor vehicles in the U.S. and Canada. It is important to note that most of these applications were initially developed using D20 as a reference. 


    In 2003 and 2009, the fourth and fifth editions were published. These were minor revisions containing a few updates that were needed to keep element definitions current with their revised uses. These editions are named:

    • Data Element Dictionary for Traffic Records Systems, ANSI D20-2002
    • ANSI D20 Traffic Records Systems Data Element Dictionary, release 5.0.0


    A new edition was published in 2016 as the D20 Traffic Records Systems Data Element Dictionary, Release 6.0.

    When D20 was first established, the ANSI process for developing standards through consensus was selected. The ANSI name not only provided a respected label, but also provided a mechanism for creating a standard that supports data definitions used across Industry, Federal and Jurisdictional organizations.  Since it was created, D20 has lagged behind the latest data definition standards and new editions merely introduced updates which were already widely in use. This was a result of the drivers of updates not being able to accommodate the ANSI process, which resulted in D20 just collecting and publishing previously approved changes.  AAMVA is dropping the ANSI process with the aim of allowing D20 to be updated more frequently so it can reflect data definitions currently being used.

    The business applications and services that AAMVA provides support the exchange of driver and vehicle data, but not the exchange of accident/crash and roadway data. As a result, AAMVA has been unable to keep the D20 updated with this type of information. AAMVA has therefore acknowledged this limitation by restricting the scope of the D20 content so that this new edition and all futures editions will no longer include data definitions for accident/crash and roadway data.

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