Dear Mr.Gentry, I'd like to couple graphviz 2.4 with Rgraphviz. First, I've installed graphviz with no errors as below: # ./configure --prefix=/usr --exec-prefix=/usr # make # make install But I got following error messages: [root at analysis Rpack]# R CMD INSTALL Rgraphviz_1.5.10.tar.gz * Installing *source* package 'Rgraphviz' ... checking for graphviz... checking for dotneato-config... not found failed configure: error: please specify a valid path to 'dotneato-config' version >= 1.12 using --with-graphviz=DIR ERROR: configuration failed for package 'Rgraphviz' However, my /usr/bin doesn't have such a file. Is there a version resriction to install Rgraphviz? or I have done something wrong (which is more likely). Thank you. Jihoon Kim