We are pleased to announce the release of DOCK 6.9. DOCK is a suite of programs for molecular docking. The source code for DOCK 6.9 is available for download and free for academic users at http://dock.compbio.ucsf.edu/. This is a release of the new ligand searching method DOCK_DN: De Novo design using fragment-based assembly. De novo design can be used to explore vast areas of chemical space in computational lead discovery. DOCK_DN is an iterative fragment growth method, in which new molecules are built using rules for allowable connections based on known molecules. For full information on what is new in DOCK 6.9, please visit: http://dock.compbio.ucsf.edu/DOCK_6/new_in_6.9.txt Sincerely, The DOCK Team Please visit us at the DOCK Web site. http://dock.compbio.ucsf.edu