Dear Dr. Tyndall, Thanks for your interest - DOCKgrid is indeed undocumented, partly because we have a much more advanced extension for viewing 3D data sets, Volume Viewer. This would let you have multiple contour surfaces or transparent solids in colors of your choosing, with interactively adjustable thresholds. The current hitch is that the DOCK grid formats have not yet been added to the Volume Viewer extension. We are actively looking into this and hope to incorporate it soon (we will let you know when this happens). I believe the values are directly those stored in the grid files, which (for dock 4 at least) are described in http://dock.compbio.ucsf.edu/dock4/html/Manual.1c.html#pgfId=850 The VDW repulsion, VDW attraction, and electrostatic grid values are described in equation 9 (all three are in the *.nrg grid). These are not in energy units until multiplied by ligand atom parameters. I believe the color choices in DOCKGrid are red and red. Display with Volume Viewer should be a vast improvement. To close molecules and also these contour surfaces, one way is to open the Model Panel (Tools... Inspectors... Model Panel in version 1.1700). In the Model Panel, choose the model(s) you want to close on the left side, then click "close" on the right side (not the Model Panel Close button). Unfortunately the contour surfaces created by DOCKgrid are each VRML files without an informative title, so it may be hard to tell which is which. If you only have one, of course, it will be obvious. I hope this helps! Best regards, Elaine =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Elaine C. Meng, Ph.D. Computer Graphics Lab and Babbitt Lab meng@cgl.ucsf.edu http://www.cgl.ucsf.edu/home/meng/index.html =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=