Le Diamant Theatre is a large-scale performing arts venue in the center of Québec City, Québec, Canada. Coarchitecture, In Situ, Jacques Plante Architects, OPI, Trizart Alliance, and Tetra Tech were chosen as the project's primary architects and structural designers to meet Quebec City's expanding needs for leisure, entertainment, and urban development. Le Diamant unifies traditional and modern architecture with the use of glass and asymmetrical design. The theater is located at the intersection of Rue des Glacis and Rue Saint-Jean, across from the historic square, Place D'Youville, in Quebec City's Saint-Roch neighborhood. Le Diamant Theatre was built over the course of three years by the Canadian construction company Pomerleau Inc., and it opened its doors in June 2019. Le Diamant Theatre was constructed for a total cost of $54 million, with an additional $10 million from the Quebec government, and the remaining money coming from private funding. New meeting rooms, offices, parking facilities, and a link between the upper and lower towns were all built as part of the project.Le Diamant Theatre's main auditorium has seating for up to 625 people. The theater holds several practice rooms, offices, and a café, as well as a smaller hall with seating for around 150 people. In addition, with the use of cutting-edge technology, such as sophisticated lighting and sound systems, a retractable orchestra pit, and a hydraulic stage, the building is created to host complex performances. Diamant Theatre's facade is covered by a large glass volume that glistens in the sunlight. The glass panels were designed to resemble diamond facets, hence the name "Le Diamant." A significant cultural icon in Quebec City, the theater has grown to become one of the main tourist destinations.