The ERO chair is a specially designed seating collection commissioned by the Croatian National Theatre (HNK) in Zagreb, following a win on their invitational competiton, as the first phase of the planned renewal of the theatre’s furniture inventory. Its name pays homage to the famous Croatian comic opera “Ero s onoga svijeta” (“Ero the Joker” / “Ero from the other world” ) by Jakov Gotovac, a work of an important status in the local theatrical tradition. The chair was designed to respond to the theatre’s distinct neo-baroque flair and exuberance without being deferential, imitative or historicist. The goal was to create an instantly recognisable seating option with a strong visual language, fit for potential application to other HNK institutions, as well as to the retail market. The collection comprises four distinct variants — two classic chairs and two barstools (with and without armrests) — tailored to meet the diverse needs of the theatre. These include furnishing the loggias, salons, supporting rooms, and the theatre café, with the option of introducing the chair to commercial sales as a signature HNK piece. Formal expressiveness and strong character of the collection both reflect and expand the identity spectrum of the HNK. Its aesthetics enhances the theatre’s ambiance and secures a cohesive visual identity across its various spaces and venues. The base construction is simple, sturdy, and minimalistic. Variations in the backrest design allow the chairs to shift from a theatrical and mildly frivolous style to a more understated and restrained appearance. Both have elements of Harlequin iconography from the Commedia dell’Arte tradition, and reflect in their lines the smile and the grimace of a comic and tragic mask. The version without the sculpted backrest offers the added benefit of stackability, allowing up to three chairs to be stacked without additional support structure, or an unlimited number with the use of a trolley. All four models of the ERO collection should ideally meet both the daily demands of a functioning theatre and the cultural aspirations of the institution they are designed for. The Chairs are developed and produced by Prostoria.