Reliability and installed cost are key parameters in the selection of the appropriate power system distribution design. This paper presents a relative comparison of reliability and costs for radial, primary selective, looped, main-tie-main, synchronous bus, ring bus, and double bus medium voltage configurations. It also examines radial, main-tie-main and spot network for tow voltage. To simplify the analysis, the alternate source is assumed always available. The derivation of the results for the medium voltage main-tie-main is shown in detail as an example to demonstrate the methodology. The advantages of the various topologies are discussed and compared.