The International Tunnelling and Underground Space Association (ITA) is the leading international organization promoting the use of tunnels and underground space through knowledge sharing and application of technology. ITA represents all aspects of tunnel and underground space planning, design and construction. Since its inception in 1974, ITA has encouraged the use of the subsurface and has promoted advances in planning, design, construction, maintenance and safety of tunnels and underground space. Currently, ITA is made up of 73 Member Nations and 300 Corporate or Individual Affiliate Members.
ITA holds, at once, its General Assembly Meeting and the World Tunnel Congress (WTC) in a different Member Nation, each year.
The Italian Tunnelling Society is an open cultural association founded in 1974 to promote and coordinate studies and research in the field of tunnel construction and great underground works. It mainly organize meetings and conferences, as well as technical visits and courses mainly focused on the sustainable exploitation of Underground. The Society aims to gather all the actors involved in the ”underground field”, with their multiple specialities and professionalisms.
The association currently consists of over 650 members, which represent public companies and organizations, universities, polytechnics, engineering companies, contractors, general and specialized firms.
SIG publishes its quarter-monthly periodical, "Gallerie e Grandi Opere Sotterranee", aimed to disseminating technical and scientific knowledge. SIG is the "Nation Member" representative for Italy in the International Tunnelling Association (ITA), and where its delegates every year participate in assemblies and Working Group activities.
SIG has successfully organized the WTC 1986 in Florence and,
together with the Swiss Tunneling Association, the WTC 2001 in Milan