The objective of this workshop is to bring together researchers studying high order mode (HOM) suppression in superconducting cavities in the fields ranging from energy recovery linacs, light sources and linear collider applications. HOMs excited by beam in superconducting cavities can create excessive heat load on the cryogenic system and dilute beam quality, giving rise to a beam break up instability in the worst case. The workshop will discuss the current status of both experimental and theoretical work in this area. Issues in electron and proton linacs, Tesla style cavities, 3rd harmonic cavities, TEM crabbing and other cavity designs will be considered. Current experiments at Fermilab, JLab, ORNL, Cornell University, and DESY will be reviewed. The event is sponsored by CST - Computer Simulation Technology (http://www.cst.com).