Avigdor Lieberman is the head of the Yisrael Beiteinu party, and is the former defense minister in the government of Benjamin Netanyahu.

Lieberman was born in 1958 in Moldova. His birth name was Evet, but when he and his family immigrated to Israel in 1978, he changed his name to Avigdor. In Israel, he served in the Artillery Corps of the Israel Defense Forces, and later earned a B.A. in International Relations and Political Science from the Hebrew University of Jerusalem.

Lieberman was one of the founders of the Zionist Forum for Soviet Jewry. He has also been a member of the Board of the Jerusalem Economic Corporation, the Secretary of the Jerusalem branch of the Histadrut Ovdim Le'umit (national workers' union) and editor of the Yoman Yisraeli newspaper.

From 1993 to 1996, Lieberman served as Director-General of the Likud movement, and then as Director-General of the Prime Minister's Office from 1996 to 1997, during Benjamin Netanyahu’s first tenure as premier.

In 1999, Lieberman founded and became head of Yisrael Beiteinu, and was elected to the Knesset for the first time, when his party won four seats. During his initial stint in the Knesset, Lieberman served as a member of the Foreign Affairs and Defense Committee and State Control Committee, and as Chairman of the Israel-Moldova Parliamentary Friendship League. In March of 2001, Lieberman was appointed Infrastructure Minister, but he resigned the post in March 2002. He was re-elected in January 2003 as part of a joint list with the far-right National Union, and received the transportation portfolio. In spring 2004 he was ousted from the cabinet by then-prime minister Ariel Sharon over his opposition to Sharon's plan to withdraw completely from Gaza.

In the 2006 national elections, Yisrael Beiteinu won 11 seats, and was initially in opposition. But after a few months, Lieberman and then-prime minister Ehud Olmert signed a coalition agreement under which Lieberman was appointed Deputy Prime Minister and Minister for Strategic Affairs. The latter position was created specifically to focus on the Iranian regime and its nuclear aspirations. Even so, Lieberman once again left the government after disagreeing with Olmert’s “land-for-peace” policies vis-a-vis the Palestinians.

In the 2009 general elections, Yisrael Beiteinu continued its rise in prominence, winning 15 seats in parliament and becoming Israel’s third largest political party, behind Likud and Kadima, and ahead of the once powerful Labor. In March 2009, Lieberman was appointed deputy prime minister and minister of foreign affairs by Netanyahu. In 2016 he joined Netanyahu's government as defense minister.

Lieberman announced his resignation from his post as defense minister and his party's withdrawal from the ruling coalition toward the end of 2018, throwing the country in political turmoil potentially resulting in early elections. His resignation came in the wake of a cease-fire agreements with Hamas, that he opposed.

Lieberman’s policies throughout the years, especially regarding a future peace solution with the Palestinians, have been controversial, and some comments about Arab Knesset members have also gained him notoriety. He has rejected previous peace formulas, such as land for peace, and has advocated transferring the Israeli Arab population to a Palestinian state, also known as the “Populated-Area Exchange Plan.” Despite being seen by many - both domestically and internationally - as an obstacle to peace, Lieberman has stated that he supports the idea of a future Palestinian state in principle. He also stated his willingness to move his wife and three children from their home in the settlement of Nokdim should Israel withdraw from the West Bank.

Lieberman has been questioned over allegations of corruption, which he has denied, and has recently been linked to an investigation into a corrupt Jerusalem building project. He has been accused of racist attitudes toward Arabs and of intolerance toward religious Jews.