The imposing towers of the Vienna International Centre were inaugurated in August 1979, joining the Stephansdom and the Prater Riesenrad as landmarks of the city of Vienna. In 1987 the Austria Center was erected nearby, hosting numerous UN conferences. More than 4.800 international employees are located here. Other international organizations like OSCE and OPEC reside in separate buildings in Vienna.

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As early as 1957 the International Atomic Energy Agency (IAEA) - and in 1967 the United Nations Industrial Development Organization (UNIDO) - have taken their offices in Vienna.

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When the United Nations Office at Vienna (UNOV) was opened in 1979, Vienna became the third official UN site.

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The United Nations Office at Vienna (UNOV) is providing organizational support for the Vienna-based UN bodies and commissions on drug control, crime prevention, criminal justice, terrorism prevention (UNODC), the peaceful uses of outer space, (UNOOSA) and international trade law (UNCITRAL). UNOV publicates information for visitors and the media and renders conference, language, postal and security services.

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The International Atomic Energy Agency (IAEA) is Vienna's largest and oldest international organization. It holds a special position, not being a UN oganization but an independent international organization reporting to the UN. Its tasks are complex, ranging from promoting cooperation in the peaceful uses of atomic energy to the monitoring of the use and stocks of nuclear material by means of a world-wide safeguards system and on-site inspections.

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The United Nations Industrial Development Organization (UNIDO) provides support to mostly agricultural developing countries in building industrial infrastructures. The goals of UNIDO have developed since its foundation in 1966: While during the first decades UNIDO helped developing countries to industrialize in order to catch up with developed countries, today UNIDO focuses on sustainable, self-supporting and ecologically sound industrial development aid.

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When the Comprehensive Nuclear Test Ban Treaty was agreed upon, the implementing agency was located in the vicinity of the IAEA, at the Vienna International Centre. The Preparatory Commission of the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO) consists of the states parties plenary body and the Provisional Technical Secretariat. The mandate provides for a world-wide monitoring system with stations built by the states and run in cooperation with CTBTO.

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Sustainable Energy for all (SE4all) is an initiative launched in 2013 by the United Nations Secretary-General to make sustainable energy for all a reality by 2030.

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Many countries have underlined the importance of the Vienna-based international organizations by establishing multilateral Permanent Missions in addition to their bilateral embassies. A special feature of UN cooperation in Vienna is called „Spirit of Vienna“, marking the willingness of delegates to work towards a consensus even on difficult topics.