In this paper, we propose a simple gaze driven shadow rendering technique, Eye Tracked Shadow Maps (ETSM), to improve shadow quality in 3D environments. We exploit the fact that human visual acuity is limited and drops off rapidly with eccentricity. We fit a shadow map to the small area on screen that falls into the user's parafoveal vision. We then combine the parafoveal view shadow map with a shadow map that covers the entire scene to shadow the scene. We built a head mounted eye tracker to track users. We evaluated our method against other shadow mapping techniques.