All technologies--hardware, software, engineering, and architecture - have positive and negative impacts on their users. In some cases, technologies like the telephone can produce liberating effects, such as not having to physically travel for a conversation. In others like the handcuff, user freedom is restricted. In the 1970s, Architectural historian Robin Evans coined these realities ‘positive’ and ‘negative’ interference. For Evans, positive interference is ‘any change in the ambient universe that allows an expansion of possible actions but does not produce any restriction...’. Conversely, negative interference, ‘involves changes that restrict possible actions without producing any extra or alternative actions that were not viable before’. Evans acknowledged that most technologies are, in fact, combinations of both. He termed this duality ‘synthetic’ giving the ordinary road as an example: “If a main road is laid along someone’s frontage it may well mean that he can cut his home / work travelling time by half. The road is giving him, in this way, more time free of speciﬁc constraints, and is therefore positive interference. But it may also mean that his wife has to ferry the kids to and from school because of the heavy traﬃc, and this is negative interference.” 1 Architecture is a highly synthetic technology. Elements that constitute the humble home such as walls, doors, windows, kitchens, bathrooms, hallways, elevators, stairs, and parking, are all hybrid performers, producing positive effects like sound insulation, security, privacy, storage of goods, and the provision of services for the preparation of food. However, the way in which they are composed during the process of building design can also produce unwanted negative interferences that lead to undesirable cognitive impact and unhappiness. How much time do Architects spend looking at the effects and potentials of negative interference? How well do Architects understand the routines and lives of their eventual building occupants, and how well designed their buildings are to minimize negative interference? As we look towards the massive amount of building needed to facilitate worldwide growth over the next 50 years - we need to ensure that building strategies are not only environmentally sustainable, but also open enough to support the dynamic desires, expressions, patterns, and routines of the increasingly diverse people they serve. As we will learn, an undesired home is the most unsustainable type of design. An open architecture is one that allows a maximum degree of desired action from its users and develops technologies or solutions for solving the restrictions of negative interference.