Cover photograph (Copyright © 2006, American Society for Microbiology. All Rights Reserved.): Chlamydia trachomatis inclusions in infected cells grown on microcarrier beads in three-dimensional suspension culture. Chlamydial inclusions were detected with C. trachomatis-specific fluorescein isothiocyanate-labeled monoclonal antibodies (green-yellow); host cells were counterstained with Evans blue (red). (See related article on page 553.)