Tasks that require fine motor ability typically favour females, whereas tasks requiring gross motor ability usually favour males (Kimura, 1999). Part of males’ advantage for gross motor movements might stem from a higher oculomotor precision in smooth pursuit (Wilner & Nakayama, 2006). Additionally, males and females search and treat information in electronic environments differently as evident from differences in scan paths (i.e. Roy & Chi, 2003). Sex differences seem to impact males and females’ everyday e-navigation differently, sometimes benefitting one sex more than the other. In this study we explore the biomechanical and cognitive underpinnings of these sex differences. We will examine eye and mouse movements using purely perceptual tasks and everyday computer tasks. To disentangle biomechanical and cognitive causes of sex differences, we will contrast performance and navigation across these tasks. Additionally, an eye-hand coordination measure based on a vector comparison method (cf. Jarodzka et al., 2010) will be developed to test for differences in cognitive load and the allocation of attention between the sexes. We expect to find differences in both navigation and performance that have both biomechanical and cognitive origins.