The London Mathematical Society is a small but important institution which operates out of De Morgan House in London. It publishes a few (very high quality) books and journals, organises and supports conferences and symposia, and has small grants to give out for mathematical activities. The LMS also bestows highly regarded prizes and medals for mathematical research. Its focus is research into pure maths.
There is a firm plan to merge the LMS with the Institute of Mathematics and its Applications (IMA), no doubt a fine institution, but one about which I must plead ignorance. Its focus is applied – or applicable – areas of maths.
There have been meetings around the country to discuss the proposed New Unified Mathematical Society, with the Presidents of both societies present (but me absent).
I can’t say that I have weighed the arguments carefully myself. But certainly several mathematicians are deeply concerned about this plan. If you have a view, you can follow the debate at their Save the LMS blog.