THC began developing software for computer-based control systems (referred to also as Direct Digital Control or DDC) in the 1970s. Microprocessor based controls can take into account many more factors and more precise interactions in operating buildings than conventional pneumatic or electric controls. Known as Dynamic Control, this family of software strategies and algorithms was among the first to employ "integrated" control strategies to take advantage of the power of these machines.

The central thesis behind Dynamic Control is that both comfort and energy efficiency are improved by intelligently managing disequilibrium conditions rather than attempting to maintain a steady state at all times. Thus, by anticipating changes and by transferring "free" sources of heating or cooling, the system maintains a dynamic, rather than static, balance. These approaches are still in use today and form the basis for much of the later software.