World Telecommunication Day has been celebrated annually on 17 May since 1969, marking the founding of ITU and the signing of the first International Telegraph Convention in 1865. It was instituted by the Plenipotentiary Conference in Malaga-Torremolinos in 1973.

In November 2005, the World Summit on the Information Society called upon the UN General Assembly to declare 17 May as World Information Society Day to focus on the importance of ICT and the wide range of issues related to the Information Society raised by WSIS. The General Assembly adopted a resolution (A/RES/60/252) in March 2006 stipulating that World Information Society Day shall be celebrated every year on 17 May.

In November 2006, the ITU Plenipotentiary Conference in Antalya, Turkey, decided to celebrate both events on 17 May as World Telecommunication and Information Society Day. The updated Resolution 68 invites Member States and Sector Members to celebrate the day annually by organizing appropriate national programmes with a view to:

stimulating reflection and exchanges of ideas on the theme adopted by the Council

debating the various aspects of the theme with all partners in society

formulating a report reflecting national discussions on the issues underlying the theme, to be fed back to ITU and the rest of its membership.