The acceptance of this book has been very gratifying. When the
publisher asked for a second edition, the writer was flattered and anxious
to make substantial additions. Those additions are scattered throughout the
book. Many experiences with client consulting have been added without
reference to client names. A certain amount of redundancy has been added
for those people that use the book by subject reference (Index). The
interchangeability and change cost have been made separate chapters in
recognition of their critical importance.