Member states

The Czech and Slovak Federal Republic ceases to exist

31 December 1992

By a letter dated 16 December 1992, the Permanent Mission of the Czech and Slovak Federal Republic (CSFR) to the United Nations in Geneva informed CERN that the Czech and Slovak Federal Republic would cease to exist on 31 December 1992 and that two new states – the Czech Republic and the Slovak Republic – would succeed it as from 1 January 1993.

The letter states:

It is the understanding, readiness and agreement of the both (sic) Czech and Slovak Republics that they will smoothly assume the total obligations of the CSFR with CERN after December 31, 1992 – develop the (sic) cooperation with CERN practically under the same conditions as the CSFR – and become full-fledged members of CERN.

Read the letter

Member states

The Czech Republic and the Slovak Republic join

1 July 1993

The Czech Republic joins

Statement of the government of the Czech Republic on questions of membership in International Governmental Organizations:

In connection with the dissolution of the Czech and Slovak Federal Republic on December 31, 1992, the Government of the Czech Republic declares the interest of the Czech Republic to be, after January 1, 1993, a fully-fledged member of the following international governmental organizations in the activities of which it has so far participated within the membership of the Czech and Slovak Federal Republic: [CERN is listed along with 51 other international organizations.]

The Czech Republic joined CERN as a member state on 1 July 1993.

The Slovak Republic joins

From CERN council minutes, 17 March 1993:

At its 297th meeting on 17 March 1993 Committee of Council discussed the accession of the Slovak Republic. Delegations indicated their unanimous support for the proposal of the accession.

The Slovak Republic joined CERN as a member state on 1 July 1993.

Member states

Bulgaria joins

11 June 1999

Bulgaria became a full member state of CERN on 11 June, when it gave UNESCO its instrument of ratification of the constitutive Convention of CERN.

At a ceremony during the council meeting, the Bulgarian flag was hoisted outside CERN for the first time to join the flags of the organization's 19 other member states. Bulgaria's deputy Prime Minister Vesselin Metodiev said that one of the priorities of the Bulgarian government is to develop and maintain competitive science in Bulgaria. "Our membership in CERN is an important step in this direction as it will enable many Bulgarian scientists, engineers and technical staff to work at the leading edge of science and contemporary technologies," he said.

CERN Director-General Luciano Maiani said: "Bulgaria's membership of CERN is another step forward in the unique European collaboration in fundamental physics research. We are delighted to welcome our Bulgarian colleagues to our community."

Member states

Israel joins

6 January 2014

From CERN press release dated 15 January 2014: 


At a ceremony today at CERN, the Israeli flag was hoisted for the first time to join the other 20 flags of the organization’s Member States, after UNESCO officially recorded Israel's accession as a new CERN Member State on 6 January 2014.

Following the ceremony, Mr Avigdor Liberman, Deputy Prime Minister and Minister of Foreign Affairs of the State of Israel, visited the LHC tunnel and the ATLAS experiment, accompanied by a delegation of officials and representatives of the Israeli scientific community.

"In my visit in CERN today, I have witnessed the frontiers of science. I have realized the scope of collaboration between Israel and CERN. Israeli scientists and their CERN colleagues share a dedication to scientific excellence, technological development and education. Israel and CERN share ideals and goals and therefore have a wide prospect for cooperation," said Mr Avigdor Liberman.

"I am very honoured as Director-General to welcome Israel as a new Member State. CERN and Israel have already a long history of mutual collaboration, and this day will undoubtedly be memorable, promising increasingly fruitful scientific cooperation between CERN and the Israeli physics community," said CERN’s Director-General Rolf Heuer.

Member states

Romania joins

17 July 2016

From CERN press release dated 17 July 2016:

On 17 July 2016, Romania became the twenty-second Member State of CERN.

Contacts between CERN and Romania began back in 1991, when a scientific and technical cooperation agreement was signed, establishing the legal framework for later developments.

Aspiring to become a full-fledged Member State and thus to contribute fully also to the governance of the Laboratory, Romania submitted its formal application to join the Organization in April 2008. The Agreement granting Romania the status of Candidate for Accession came into force on 12 November 2010.

Romania's scientific community at CERN has grown over the years and currently numbers around a hundred visiting scientists. Romania has particularly strong presence in the LHC experiments ATLAS, ALICE and LHCb. Romanian researchers and engineers also work at DIRAC and n_TOF at the Proton Synchrotron (PS), on the NA62 experiment at the Super Proton Synchrotron (SPS), and at the ISOLDE facility. Romania is also active in the Worldwide LHC Computing Grid.

Read the press release here.

Member states


Subscribe to Member states

You are here