First published in 1980 as "A Passport with Machine Readable Capability", Doc 9303 is now published in three separate Parts.

Part 1 - Machine Readable Passports

The Sixth Edition, in two volumes, was published in September 2006. Volume 1 set forth the specifications for a machine readable passport (MRP),  characterized by a visual inspection zone and a machine readable zone (MRZ) containing essential identification and document details in OCR-B typeface. Volume 2 Sets forth the specifications for biometric enhancement of the MRP to become an "e-Passport".

Part 2 - Machine Readable Visas

The third Edition was published in 2005. Specifications provide for a visa format in two sizes - Format A, sized to fill a passport page, and the smaller format B. Like the MRP the machine readable visa is a standard format consisting of a visual inspection zone and a machine readable zone. However, the Third Edition requires that a space be provided for a portrait of the holder, and fewer layout options than the previous edition allowed.

Part 3 - Machine Readable Official Travel Documents

The third Edition, Part 3, published in 2008, updates and replaces the specifications for machine readable official travel documents as published in the second edition (2002) and represents a substantial modernization of the material contained in previous editions. In particular, this third edition incorporates the optional new globally interoperable standard for biometric identifcation of the holder and for the storage of the associated data on a contactless integrated circuit. Volume 1 is an updated version of the second edition containing all the specifications required for a State wishing to issue a machine readable official travel document without the incorporation of machine-assisted biometric identification. Volume 2 contains the specifications for enhancing the machine readable official travel document with the globally interoperable system of biometic identification and its associated data storage utilizing a contactless integrated circuit.

Specifications common to all parts are:

• recommended transliterations of national characters, and
• 3- letter codes for nationality and the issuing entity.