Techniques for improving sound barriers through the use of lead sheeting are described. To achieve an ideal sound barrier a material should consist of the following properties--(1) high density, (2) freedom from stiffness, (3) good damping capacity, and (4) integrity as a non-permeable membrane. Lead combines these desired properties to a greater extent than any other common building material. The proper use of lead in combination with other materials can compensate for their deficiencies and improve the acoustical performance of the composite barrier. Three ways in which barriers are rated for their effectiveness are discussed and compared. Practical tips for designing better sound barriers as well as pitfalls to be avoided are listed. Design and construction information for installing practical lead walls is presented and guidelines are recommended. (TG)