The architecture and construction sectors have been driven towards innovative design aimed at reducing energy demand in whic zero energy buildings became a leading paradigm for sustainable solutions. This chapter explores tools for performance forecasting and process optimization from the early stages of building design. Particularly, tools including energy performance assessment models, machine learning techniques, and dynamic simulation engines to direct energy efficiency optimization from conceptual to operational phases. The impact of educational programs, accreditation systems and the industry co-operation on spreading expertise and acceptance of zero energy buildings principles were also discussed. Presented case studies examine some of the best practices, challenges and opportunities that accompany zero energy buildings implementation.