The Castle in 3 Acts, was a disciplinary action in the city of Guimarães which included theater, performance, exhibitions, conferences, literature and a film cycle. Placed in the context of Guimarães 2012, the project concept, seeks to meet the event structure and the concept that it is adjacent and was developed by the commissioner Paulo Cunha e Silva. The developed concept tried to set up a language that is adaptable to all areas that the project covers from art, architecture, music, literature and cinema. The concept of this project works with the metaphor of the castle, and this figure of speech allowed that the language that was created to communicate the C3A, was as versatile as possible in their applications and readings. The project justified, by its size and features, the creation of a unique identity within the universe ofGuimarães 2012 communication. This identity reflects the metaphor of the castle, proposed by the exhibition Commissioner Paulo Cunha e Silva and serves as the basis for the whole communication. The concept covers a parent brand and sub-brands that are differentiated by their formal and chromatic morphology assigned to various areas. For the event were produced numerous pieces of communication (invitations; mupis; outdoors; banners; website; signage, catalog; flyers, …) that due to their functionality and purpose special care had to reinforce the concept that production of the project.