Reducing school district energy expenditures has become a universal goal, and new technologies have brought greater energy efficiencies to the school environment. In Part 1 of this two-part series, the author discussed the steps required to establish an energy conservation and management program with an emphasis on lighting. In this article, he reviews heating, ventilation, and air-conditioning (HVAC) systems and the newer technologies that offer some interesting opportunities for school officials. Retrofitting HVAC systems requires architects and engineers who have a thorough knowledge of the newer equipment and their associated technologies. Differences in building characteristics, such as insulation, age, and construction, should be considered when contemplating energy savings. [For Part 1, see EJ981972.]