Founded in 1974 by the initiative of nineteen Nations, the International Tunnelling and Underground Space Association (ITA) which aims are:
- to encourage the use of the subsurface for the benefit of public, environment and sustainable development and
- to promote advances in planning, design, construction, maintenance and safety of tunnels and underground space, by bringing together information thereon and by studying questions related thereto.
Since then, ITA has considerably developed. Presently, ITA gathers 78 Member Nations and 266 Corporate or individual Affiliate Members.
The General Assembly, which met annually, resolves all questions concerning the organisation and conducts of the affairs of the Association; it shall approve the budget of receipts and expenditure, and appoint and organise all Committees of the Association; it shall decide on the admission of new adhering national Organisation and of the new affiliate member.
The General Assembly is host by a Member Nation at the occasion of the yearly World Tunnel Congress.