The research reported here is based on dialectological fieldwork among Lebanese Jews from 2006 to 2015. In the 20th century most Jews of Beirut lived in the Jewish Wādi ˀAbu Žmīl quarter, an area measuring 300 metres by one kilometre. Very few families lived in other parts of the city. The Beirut community consisted of Jews originally Lebanese, Syrian Jews from Aleppo and Damascus, numerous Ashkenazi Jews, Jews originally Maghrebi, some Kurdish Jews, Jews from Turkey and Greece, especially Salonika, and Sephardi Jews originally from Andalusia who reached Beirut after their expulsion from Spain in 1492. The Beirut Jews’ dialect differed from that of the Sidon Jews, but in many respects also from the dialects of the Beirut Arabs, lacking highly typical phenomena such as the Imāla. Like diverse other Modern Judeo-Arabic dialects, this one embraces the vast array of vocabulary used in Jewish life. At its height Beirut’s Jewish community numbered several thousands, but over time it dwindled and disappeared — together with its dialect. Most of its speakers left, many of them for Israel, where the fieldwork was undertaken.