The work carried out within the five permanent technical committees resulted in the publication of “UIC leaflets”, technical documents whose application was either obligatory or optional. These technical leaflets constituted the beginning of an international railway “code”, also known in practice as the “UIC Code”. Initially published in French and German (with an English version also available today), these leaflets formed part of the “set of UIC decisions”. In 1932, there were 103 leaflets and by 1938.. At their peak there were close to 700 leaflets covering all the main areas of railway activity: Statutes and Regulations, Passenger and Baggage Traffic, Freight Traffic, Finance-Accounts-Costs-Statistics, Operating, Rolling Stock, Traction, Way and Works, Technical Specifications and Information Technology. Since 1999, the UIC Code has been computerised and the leaflets are available on CD-Rom and on the website.

Today, we are in the process of converting leaflets into IRSs.