This report describes the development of establishment criteria for the standard Microwave Landing System (MLS) with approach lights. The criteria were empirically derived from a benefit/cost analysis. The key elements of the criteria are expressed as a function of (a) annual instrument approaches (AIA's) by user category, (b) non-precision approach minima on the candidate runway, and (c) the probability of IFR weather at the airport. It is estimated that through 1985, the criteria will identify 218 new MLS candidates. Through 1995 the number of potential candidates is expected to reach 324. In addition to these systems, there will be approximately 768 systems in the ILS inventory that will be replaced by an MLS in accordance with guidelines developed in FAA's Microwave Landing System Transition Plan. This represents 1092 (768 + 324) or approximately 1100 systems by 1995. Benefits of an MLS vary widely depending on the proportionate use of the MLS runway, the distribution of instrument weather at the airport, aircraft operating costs, average number of passengers, and other factors. The MLS candidate runways, after first being qualified by regional offices on the basis of establishment criteria published in Airway Planning Standard Number One (APS-1), will then be evaluated by a benefit/cost analysis at FAA Headquarters.