The Office of the Chief Rabbi will have a new chief executive when Rabbi Ephraim Mirvis takes his post in September.
Ari Jesner, 37, a lawyer with Berwin Leighton Paisner in London, will become the new Chief Rabbi’s right-hand man.
Joanna Benarroch, the officer’s current director of the office, will leave to continue to working for Lord Sacks.
Mr Jesner, who is originally from Glasgow, is chairman of the Yoni Jesner Foundation, a charity set up in memory of his youngest brother who was killed in a terrorist attack in Jerusalem 11 years ago.
He is a member of Finchley United Synagogue — the community that Rabbi Mirvis headed until he left in April to prepare for the chief rabbinate.
Rabbi Mirvis said: “Ari is a man of immense talent, wisdom and grace. He brings with him a wealth of experience from the professional world and deep knowledge of the Jewish community.”
Mr Jesner said: “I look forward to working with Rabbi Mirvis and to help him implement his vision as he embarks on his chief rabbinate. This is a very exciting time for the Jewish community as we begin a new journey.”
Mr Jesner, who is married with three children, is a former national executive member of Bnei Akivah and has been involved with educational programming at the London School of Jewish Studies.