Advertising agencies have a growing interest in finding out if roadside advertisements have reached the target audiences. The drivers’ head position’ would enable us to determine if they have been looking at the billboards. Numerous researches were focusing on the drivers’ attention from inside their cars; however, some have tried to determine the interaction between the drivers and outside objects. In this paper, the proposed Head Pose Estimation (HPE) is able to detect drivers’ head motion/position and try to determine if they are looking at the billboard. This information is vital for the Advertising companies for the evaluation of the effectiveness of their advertisements.