English: As a result of the 1992 United Nations Conference on Environment and Develop ment (UNCED) Earth Summit Conference in Rio de Janeiro, 180 nations adopted a program called Agenda 21: an international attempt to create a normative blueprint for sustainable development worldwide. It is, however, not really pos sible to define a normative blueprint for the whole spectrum of human settle ments worldwide, as economical, ecological, geographical, topographical and social contexts differ. In informal settlements, especially, design criteria for sus tainable development are of paramount importance. While this paper exam ines these problems from an international point of view, it does so in a South African context. Problems in five subsystems (political, economical, sociocul tural, environmental and technological) are examined. Recommended solu tions are summarised in tables of design applications concerning the site selection; passive solar design; watersaving measures; sanitation options and applicable energy conservation measures. To dispel possible doubts concern ing the use of traditional materials and practice, a further summary has been compiled to show the benefits gained by using these alternative construction methods, expounding vernacular building methods that have traditionally been used in South Africa and in similar climatic conditions elsewhere.