Hi Sorry I have posted my last message without read of your message. I just read your message. Actually I have run yum update on my system and now again the configure command is complaining about CGAL directory not found.However CGAL folder is available in /usr/include. 1. what is right procedure to build CGAL. I execute "cmake ." and "make" commands to build CGAL but all header files and library files created in the same directory where CGAL source files are there. after that I copy the CGAL folder under /usr/include is it the right way? 2. I set environment variable: CXXFLAGS="-L/usr/include" is it ok? your help would highly be appreciated My system is in office I will run it again and will send config.log file to you in the morning. Many Thanks for your help -- View this message in context: http://main-discussion-list-for-the-graph-tool-project.982480.n3.nabble.com/... Sent from the Main discussion list for the graph-tool project mailing list archive at Nabble.com.