Two trends are likely to define the 21st century: threats to the sustainability of the natural environment and dramatic increases in urbanization. This paper reviews the goals, business models, and partnerships involved in eight early "ecocity" projects to begin to identify success factors in this emerging industry. Ecocities, for the most part, are viewed as a means of mitigating threats to the natural environment while creating urban living capacity, by combining principles of green building with the use of information and communication technologies (ICT) to better manage complex urban systems.