High occupancy/toll (HOT) lanes allow travelers to pay a toll to enter a high occupancy vehicle (HOV) lane when they do not meet the minimum occupancy restrictions of the lane. In cases where HOV lanes are not utilized to their full capacity, this provides an effective, and controlled, use of that spare capacity along with a revenue source to offset expenses. Although this is a promising concept, and many cities around the United States are examining the potential development of a HOT lane, only four HOT lanes currently exist. This research documents the findings of six years of experience with two HOT lanes in Houston, Texas. This includes an examination of the daily number of paying customers on the HOT lanes, benefits of the HOT lanes, socioeconomic and commute characteristics of HOT lane users, and their mode of choice when electing not to use the HOT lane.