Bio++ is a set of C++ libraries for Bioinformatics, including sequence analysis, phylogenetics, molecular evolution and population genetics. Bio++ is Object Oriented and is designed to be both easy to use and computer efficient. Bio++ intends to help programmers to write computer expensive programs, by providing them a set of re-usable tools. This contains the Bio++ 1.9 (April 2010) Seq Library. It can be installed along the current Bio++ suite libraries, however they better not be present at compile time.