After résumé of the fungi encountered in leather technology, asepsis is discussed with special reference to shoe works for tempering soles, for rendering newly worn shoes antiseptic rebuilding of foot wear and for combined disinfection and stain prevention of insoles. Next, some observation are made on a well know household antiseptic and also on the halogenated phenolic group. A discussion then follows of the mould growth in relation to foot perspiration, leading to entirely original technique for routine adoption that can be well-recommended both for leathers and fabric linings. The superiority and merits of phenyl mercuric nitrate are again considered and a number of alternation discussed of which, sodium silicon and boron fluorides can be recommended. Best thanks are due to the writer's colleague, L.P. Huggett, M.Sc., A.R.I.C., for much assistance in the practical work and to the Director and Council for the loan of the photograph and for permission to publish. -- CAL