I develop code to run on multiple processor machines. Moderate use of the standard template library (STL) containers cause programs to slow down when the work is split between threads running on different processors. This is because the STL default memory allocator is a thread-safe singleton and causes contention between the threads. The memory allocator provided by boost::pool_allocator is also a thread safe singleton. I have coded a thread specific memory allocator based on boost::pool and boost:thread_specific_pointer. My allocator creates a new instantiation for each thread it is used in, and so avoids contention between threads. The containers created with this allocator must be used carefully, not written to by more than one thread, because the allocator is not thread-safe ( that is the point! ) - however they provide dramatic performance improvements when my code runs on multiple processors. I do not expect my coding is to the high standard of the boost libraries, but I do believe it shows that something very useful can be done with a few lines of code. Any chance of a boost:thread_specific_pool_allocator in the near future? James Bremner