This file spells out the requirements for building RNAstructure. *nix installation of text interfaces: Installation for Unix, Linux, or Mac OS-X requires a current C++ compiler. building.txt provides instructions for building the package. Windows GUI or text interface building: Building the Windows programs requires Microsoft Visual C++, version 2005 or later, and the Intel C++ compiler, integrated into Visual Studio. The GUI solution for Visual Studio is found in the RNAstructure_windows_interface directory. A text interface solution is found in the RNAstructure_windows_text_interfaces directory. JAVA interface building: To build the JAVA interface, the Sun JAVA JVM, version 1.6 or later, is required. The version of the JVM that comes from the JDK (Java development kit) is essential, because the headers in the "include" directory are necessary for successful integration of the interface with the back end. The JAVA interface can be run by executing RNAstructure.bat in the exe/ directory, after shared libraries have been built in that same location. In compiler.h, variables INCLUDEPATH1 and INCLUDEPATH2 must be set (see compiler.h for details). ** Note that using other JVMs than the Sun JVM may cause aberrant program behavior and/or crashes.