The fourth and probably last edition of Agaricales in Modern Taxonomy is again fully revised and updated. The basic concept and the system of classification have not changed even though some mostly minor rearrangements have been accepted or introduced.
Changes in the classification from the third to the fourth edition will be evident to the reader if he compares the respective surveys of the genera of Agaricales Aside from the introduction of a few new genera – their number has now risen to 230 – and generic synonyms, the most important changes are (1) the introduction of three suborders, (2) the transfer of Omphalotus and Lampteromyces to the Paxillaceae, (3) the discussion of the reasons for acceptance or non-acceptance of important proposals published in the period between 1975 and 1985, some as important as those by Kühner (1977-1979).