As is well-known, the definition of regional styles in Romanesque art and architecture has long been associated with the existence of ‘schools’. The concept emerged in the 19th century, and this paper addresses the issues raised by the problematic category of ‘schools’ in relation to the so-called Wormser Bauschule (Worms school of builders). The discussion will be focused on one particular decorative form invented in the workshop of Worms Cathedral at the beginning of the 12th century and then follows its deployment in other buildings in the city, in the region, and beyond – thus touching on issues related to transregional styles. This form, in German Hornauslauf (horn-stop), is a particular type of ending applied to the vertical profiles of pilaster strips. Tracing the progressive use of the Hornauslauf, it will be asked how and by what means this form spread. Does this mark the activity of a ‘school’? Or, rather, is ‘school’ the right concept by which to group and define different workshops active in the city of Worms, its region, and beyond? Should we talk about a ‘school’ or a specific workshop, or are some forms disseminated by single masons?