Growth and reproduction are two of the most fundamental processes for plants. After a plant produces biomass, it allocates this biomass to different structures and functions, among them reproduction. It has become clear that most allocation patterns are allometric, so the concept of "reproductive effort" is being replaced by "reproductive allometry". While there has been much recent research on broad allometric scaling relationships among species, the allometry of reproduction within populations is a very different question, which is central to plant population ecology and evolution, but has not been given sufficient attention. This session will focus on patterns of size-fecundity relationships within plant populations. Questions to be addressed include: (1) Are there one or more general patterns of size-dependent reproductive output within different plant species and populations? (2) When are size-fecundity relationships plastic, and when is reproductive output solely a function of plant size and fixed allometric allocation patterns? (3) What do patterns of reproductive allometry tell us about plant strategies and constraints?