In a natural infection, human papillomavirus (HPV) replicates in a stratified and differentiated epithelium. We have developed an in vitro organotypic raft culture system that allows researchers to study HPV in its natural environment. Not only does this system reproduce the differentiation-dependent replication cycle of HPV, but it also allows for the production of high titers of native HPV virions. Currently, much of the HPV research has been done utilizing synthetic particles produced in transfection systems. However, by production of native virions, this research can now be continued using native particles. This chapter presents methods for producing, titering, and qualitating, via infectivity assay, native virus produced from organotypic raft culture.