Most major topics that bear on the lophophorate condition have been ably treated in preceding contributions for either the Bryozoa or Brachiopoda. Accordingly I shall attempt a comparative approach, first characterizing the lophophorates as a whole and then contrasting the groups with an eye towards the evolutionary implications of resemblances and differences. To set a practical target I shall attempt contrasts between the feeding systems, because they seem to be particularly important to the present habits, habitats and distribution patterns of these groups. From this approach, questions naturally arise as to the evolutionary history of the lophophorates and in particular of extinct types of Brachiopoda for which modern analogues are unknown; these problems form potential research areas of special interest. To conserve space I have tried where possible to cite only more recent and/or general works that themselves contain ample references. I have assumed that by this point in the volume the reader will be acquainted with the gross morphology of bryozoans and brachiopods and with the major descriptive terms applied thereto. Because phoronids are not specifically covered in other contributions, I have included a wider range of phoronid references including some historically important works.