As a minority within a minority, the Dublin Jewish Progressive Congregation (DJPC) barely features in the history of either Irish Jewry or Britain’s Liberal Judaism (LJ) movement. Any discussions of the congregation have been superficial; it is dismissed as religiously lax in the orthodox-led, largely anecdotal Irish Jewish historiography, but as conservative in the LJ context. This article critically examines the DJPC in its own right and “from within” for the first time, drawing on local memory and a range of material, personal and archival. I begin by querying exactly what the synagogue’s founders were seeking to achieve in establishing an Irish outpost of Jewish reform. The incremental development of a distinctive Irish brand of progressive Judaism is then investigated through the formative influence of the DJPC’s primary institutional relationships: that with the local orthodox community, and that with the Union of Liberal and Progressive Synagogues (ULPS) in London.