Although the effect of shapes on area and volume perceptions has been documented in psychophysical and marketing literatures,little attention has been given to the relationship between elongation and pouring or consumption volumes.We extend the work by Wansink and Van Ittersum (2003) by relaxing the assumption that the amount people intend to pour is independent of the capacity of the container.We examine situations where people focus on the proportion of the content relative to the container (i.e.,a target proportion) when determining the pouring volume.Using a system of psychophysical models and two experiments,we demonstrate that the elongation of the container positively influences the pouring volume and this effect is moderated by the target proportion.Our results highlight the importance of understanding target proportion and its effect on consumers’ judgment and decisions,which also have very important managerial and public policy implications.