The purpose of this project was to investigate sitting pressure distribution in manual wheelchair users while propelling across different surfaces, and whether differing terrain would generate more significant pressures on the sitting surfaces compared to others. Sitting pressure refers to any pressure experienced by any body tissue while sitting but is generally on the buttocks, dorsal thighs and lower back for individuals who can maintain a typical sitting posture of flexed ankles, knees, and hips along with an upright torso that is in midline. Wheelchair sitting pressure was measured on 39 adult novice wheelchair participants. Participants self-propelled and were pushed across three surfaces. Results were that self-propulsion generates greater sitting pressure on the wheelchair user compared to being pushed across three different surfaces of carpet, tile and concrete (ps <.0167). The integral pressure was greater during passively traversing on carpet compared to concrete (p=.002). During active propulsion, carpet elicited greater pressure than both tile and concrete surfaces (ps<.0167). Occupational therapists should consider the impact that passive versus active wheelchair propulsion and floor surfaces have upon wheelchair sitting pressure.