The object of this paper is to show the importance of properly designing an underground distribution system for the district it serves and the particular service it is to supply. Simply placing the wires underground does not constitute an efficient system. Underground distribution is the ultimate solution of the distribution problem that confronts every Electric Light and Power company operating in progressive towns and cities. The excessive cost of this class of construction, as compared with aerial construction, and the permanent nature of the system, warrant a careful study of the conditions and justifies a reasonable expense in the development of suitable plans for the system. The financial success of an electrical undertaking depends on supplying efficient and reliable service in an economical manner, and in order to secure this result the distribution system must be carefully designed and properly installed. The automatic substation, when perfected and adopted, will not only permit a great reduction in the number of ducts required and a lower first cost, but will provide more reliable service and bring underground distribution within the reach of many small companies where the cost of this class of service would not be warranted under the former conditions. The suggestions offered in this paper are based on many years experience and are made with a sincere desire to aid those interested in this class of work, particularly in the design and installation of the first system in the smaller cities.