The ease with which posture changing occurs in pigs has welfare relevance since the duration of lying down and standing up behaviour may indicate the adequacy of floor type to give security of movement, and/or the mobility of animals after resting on floors differing in comfort. Standing and lying behaviours consist of a predictable sequence of movements, with stages between movements when the animal can pause in a relatively stable transition state. In sows, it has been suggested that the duration of one or more of these stages might be sensitive to both animal and environmental factors (Marchant and Broom, 1996); however whether this is the case in finishing pigs is less certain. The aim of this study was therefore to evaluate behaviours indicative of both the physical comfort of different types of floors and security of movement in finishing pigs.