This study investigates whether or not non-traditional marketing has an effect on the prices paid for residential real estate. Non-traditionally broker-marketed properties are defined as those properties that are sold with the aid of a real estate broker, but not marketed through a Multiple Listing Service (MLS). An analysis of properties that sold in this fashion offers further insight into the intermediation role of the real estate broker, as well as an opportunity to further investigate the efficiency of residential real estate markets. Specifically, we can assess whether MLS participation generates higher prices by determining whether like-kind properties price equivalently despite differences in their mode of marketing. The results show a significant and positive impact by non-traditionally broker-marketed properties on property price suggesting, for this sample, a premium of over 6% compared to like-kind properties marketed through the MLS. This premium may be a result of brokers intermediating a better matching of buyers and sellers. The observed premium also suggests a degree of market inefficiency. Copyright Springer Science + Business Media, Inc. 2005market efficiency, intermediation, principal-agent, residential brokerage,