The case is presented for meeting energy efficiency requirements by using the site-cast tilt-up construction method. Although solid concrete panels have low thermal resistance, the thermal characteristics may be improved by the use of added insulation. The benefits of concrete are provided by its mass, which enables the building to absorb heat during the hottest times of the day, and gradually release it during the coolest. This helps to stabilise the internal temperature. The density of the material also minimises the passage of moisture and air, whilst the large unit size reduces the number of joints. Award winning examples of tilt-up use in Austin, Texas and San Diego, California are briefly described. 2 refs.