MOLDEN: A Portable Electron Density Program by Gijs Schaftenaar,Caos/Camm Center,Faculty of Science,University of Nijmegen,P.O. Box 9010,6500 GL Nijmegen,The Netherlands MOLDEN is a package for displaying Molecular Density from the Ab Initio packages GAMESS* and GAUSSIAN (* referred to here is the european version of GAMESS maintained M.F. Guest et al, not to be confused with the american version maintained by M.W. Schmidt et al). MOLDEN reads all the required information from the GAMESS/GAUSSIAN outputfile. MOLDEN is capable of displaying Molecular Orbitals, the electron density and the Molecular minus Atomic density. Either the spherically averaged atomic density or the oriented ground state atomic density can be subtracted for a number of standard basis sets. MOLDEN supports contour plots, 3-d grid plots with hidden lines and a combination of both. It can write a variety of graphics instructions; tekronix4014, hpgl, postscript, XWindows, hp2392 and Figure. For the Silicon Graphics there is a version taking advantage of the 4D Graphics library. The X-window version of MOLDEN is also capable of importing and displaying of chemx, PDB, and a variety of mopac/ampac files. Lines of Code: 7200,834 FORTRAN 77,C (VAX,SUN,CONVEX,APOLLO,DEC/Ultrix,IRIS,Cray-YMP/Unicos HP,RS6000,DEC Alpha)