This grant supports a symposium is on the kinetics of diffusional phase transformations. The emphasis of the program is to focus on essentials of theory of homogeneous nucleation and how it compares to experimental results. The symposium considers all three common states of matter, as follows: seven papers on homogeneous nucleation theory; six papers where homogeneous nucleation theory is compared to experiments in which the reactions, solid -> solid, metallic glass -> crystalline solid, liquid -> solid, and vapor -> solid nucleation, take place; eight papers in which nucleation and/or growth theory are applied to fundamental and practical problems. The symposium honors the late G. Marshall Pound, a distinguished scientist who worked effectively in this field of research.