Hi all, The first version of submitted library container_bptree http://www.boostpro.com/vault/index.php?action=downloadfile&filename=container_bptree_01.zip&directory=Containers& offers a number of STL variants of containers based on B+ trees. These powerful data structures enable the implementation of various useful extensions of STL containers and iterators. One of the most interesting improvements is the efficient algorithm accumulate(), which has computational cost *O(log N)* in the worst case. This algorithm can increase performance of solutions in numerous application areas, including traveling salesman problem. Please read the documentation and try the included test code. The current implementation has been developed for Visual Studio compilers (2008 and 2010). Portability of this library has not yet been tested. I would really appreciate if someone could compile and run the test code using other compilers and let me know if there are any technical issues. Any suggestions concerning improvements of the current version of this library will be carefully analyzed and implemented if possible. The potential of B+ trees has not yet been used to its full capacity. There are a number of options for further extensions of this library. The community interest and feedback will have an effect on the priority of the development of new features and efficient algorithms in future versions of this library. Thank you, Vadim Stadnik