The next-generation electric grid needs to be smart and sustainable to simultaneously deal with the ever-growing global energy demand and achieve environmental goals. In this context, the role of residential and commercial buildings is crucial, due to their large share of primary energy usage worldwide. In this chapter, we describe energy management frameworks for buildings in a smart grid scenario. An Energy Management System (EMS) is responsible for optimally scheduling end-user smart appliances, heating systems, ventilation units, and local generation devices. We discuss the performance and the practical implementation of novel stochastic MPC schemes for HVAC systems, and illustrate how these schemes take into account several sources of uncertainties, e.g., occupancy and weather conditions. Furthermore, we show how to integrate local generation capabilities and storage systems into a holistic building energy management framework.