Britain's oldest community, the Spanish and Portuguese Jews' Congregation, has become the first of the main Orthodox synagogue bodies in the UK to allow women on to its executive.
Members of the 350-year-old institution, which comprises four London synagogues, approved the change as part of a constitutional overhaul.
Women will now be able to form up to a third of the Mahamad, the executive committee, whose membership will be increased from five to six.
At the same time the board of elders, which has women members, will be cut from around 30 to 16, including the Mahamad, when new elections take place in June.
The changes were agreed by the Sephardi Beth Din, though women will not undertake ritual duties in the synagogue.
Alfred Magnus, president of the elders, said the development was "the result of excellent co-operation between elders and Mahamad over the last two years, following a number of earlier attempts to modernise our governance."
Traditionally the executive have been known as the "gentleman of the Mahamad". How they will be referred to in future has yet to be settled.