The contributors to this volume have all participated very actively in the fascinat-
ing adventure of the development of renal replacement therapies, which actually has

been one of the core issues of their professional life. The editor is most grateful to
them for having devoted much of their time and effort in order to enable the readers
to benefit from their long-term experience in their respective area of expertise.
Data reported in several chapters of this book are based on (or taken from) the
annual reports of the United States Renal Data System. The interpretation and
reporting of these data are the responsibility of the authors and in no way should be
seen as an official policy or interpretation of the US Government.