An important factor in the choice of a pacemaker ought to be its reliability following implantation. Unfortunately, as the total number of patients increases, handling of basic data becomes a tedious and time consuming task. Analysis of data becomes an even more arduous task. Proposals are made for somputer storage of pacemaker data so that regulare up-dated "print-outs" can be made available. Analysis by computer then becomes a trivial task. The advantage of a single data handling centre for the whole of the United Kingdom is particularly attractive.