Road traffic characteristics are affected by various elements, including carriageway width, surface features, terrain conditions and driver skills. Additionally, the activities on or near the edge of the road influence traffic performance. The term ‘side friction’ refers to the activities on the sides of the roadway interacting with the traffic flow. The extent and severity of such components are exceptionally high in mixed traffic conditions. Among the various elements responsible for roadside friction, pedestrian flow through undesignated road space is a recurring issue in all midblock sections. In the absence of adequate and well-designed infrastructure facilities, pedestrians use the regular carriageway for movement and crossing, which disrupts the traffic flow. Due to the forced reduction in speed or path change to avoid collision with pedestrians, vehicles often experience delays. Eventually, the functionality of the section is adversely affected, and the capacity gets reduced. Movement through these unprotected locations creates safety issues for pedestrians also. Although it is widely accepted that side friction factors like pedestrian flow affect the speed, capacity and level of service of facilities, only a few studies have attempted to quantify them. If these activities are properly addressed and regulated, traffic performance may be enhanced, and such measures may produce greater economic benefits. This paper is intended to focus on different approaches for quantifying the effects of pedestrian flow on traffic characteristics under mixed traffic conditions. Future research directions in this area are also discussed.