Protected left turn phases are typically added at signalized intersections to increase left turn capacity and improve left turn traffic safety However, each additional phase added to the signal operation has the potential to increase the cycle length and increase the overall delay of the intersection. Typically the traffic engineer, based on peak traffic demand determines the choice of the left turn traffic treatment. This choice is used for most of the day. Very few traffic engineers have the resources/information to use a different left turn treatment at different times of the day. This results in protected or protected/permitted left turn treatment being used the entire day. Frequently, this will result in the left turn phase being used to serve one or two vehicles, when the same vehicles could have been serviced in the permitted portion when there are significant number of large gaps in the opposing through traffic movement. To solve this problem, researchers at Texas Transportation Institute (TTI) developed an "Adaptive Left Turn" routine for a signal controller. Automatic Signal/Eagle signal incorporated this feature in their EPAC 300 controller's logic. This feature was tested at TTI in a preliminary study. This study determined the traffic conditions where this feature could be used effectively. The current study used these recommendations and implemented the feature at an intersection in College Station, Texas. The study specifically evaluated whether "protected/permitted" operation could be satisfactorily replaced by "permitted only" operation when traffic conditions were appropriate. This paper documents the results of this field implementation of this feature in the EPAC 300 controller. The primary objective of this field implementation is to field test the functionality of the feature available within the controller to improve intersection operations.