Of course, a designer must know the technical performance capacities of materials, such as their durability or strength, but it is not this pragmatic aspect of performance that I want to consider here. Instead, I am taking the uncomplicated, non-theatrical, meaning of performance as 'the doing of an action'. Part of the event of an interior concerns a relationship between matter and people, and what each does with, or to, the other. Both the animate and the inanimate are protagonists in this event. The performance that I wish to discuss is 'what is happening' as a result of the complex entanglement of these things in this place with these people at this moment in time.