RPVM: Cluster Statistical Computing in R. rpvm is a wrapper for the Parallel Virtual Machine (PVM) API. PVM (Geist et al., 1994) is one of the original APIs for extending an application over a set of processors in a parallel computer or over machines in a local area cluster. We discuss the PVM API, how it is implemented in R, and provide examples for its use. rpvm provides a quick means for prototyping parallel statistical applications as well as for providing a front-end for data analysis from legacy PVM applications.