Abstract The Italian sindacato was a procedure that from the end of the twelfth century held major officials accountable and exposed them to public control. While the sindacato presented citizens with the opportunity of bringing forward their claims against officials, the evidence of these claims and their outcomes are sketchy. Recent historiography often portrays this procedure as a rhetorical device of civic order and legitimation that only produced real consequences when used as a tool for the political purposes of the elite. The article focuses on Siena, often singled out for the popular character of its governments, as a unique case to test the actual popular participation and oligarchical involvement in sindacati and their significance in relation to the sindacati in other communal cities. First, it analyzes the wide spectrum of participants in the procedure and, in particular, the interests at play for common actors. Second, it explores the direct relationship between sindacati and other institutions and systems of accountability within the city, as well as their interdependent transformations over time. The result is a revision of sindacati that reintegrates the agency and participation of popular actors. The sindacato appears then as neither a zenith of communal democracy nor a crooked tool in the hands of oligarchical interests, but rather as a central act of civic life articulating a wide range of interests among all sorts of citizens, which allowed for its symbolic relevance to perdure until the Renaissance and beyond.