The subject files document the entire period of Thomas Leming's association with MCI. The main topics addressed in the files are negotiations for the right of way to construct telecommunications routes, and various telecommunications technologies such as microwave and fiber optics. Also documented are the evaluation of technical equipment by MCI staff, and negotiations with vendors over the lease or purchase of technical equipment. Document types in this series include maps of telecommunication systems, correspondence, memoranda, and technical reports. Also included are draft and executed copies of agreements reached by MCI. The group also contains applications to the FCC, copies of purchase orders, and railroad maps of those railroad companies whose rights of way were of interest to MCI. Records are arranged alphabetically by folder title, with original folder title maintained whenever possible.