This update briefly reviews some of the principles of sustainability which require the attention of applicants and approval authorities, especially relevant in the consideration of development applications for multi-residential construction. In New South Wales, Australia, this issue is dealt with almost exclusively under the SEPP BASIX regulations. The paper comments briefly on some trends under BASIX, withsome prognosis for the future. Within the broader framework of sustainability concerns, the two amenity requirements of solar access and natural ventilation have become increasingly influential determinants of the architectural design of apartments. Because they are often poorly understood, both have tended to be interpreted rather mechanically both by designers and Council officers. This paper highlights some experiences when one approaches these amenity issues with greater technical sophistication.