Originally I tried to separate the mere typographical errors, the more substantial mathematical errors, and the addenda (i.e., things that aren't actually errors, but just comments about what I wish I could add to the book). But I've decided that it's not really possible to separate those categories -- there's too much overlap.

For convenience this list is now broken into several web pages, one for each "part" of the book:

1. errata & addenda for the preface and SETS AND ORDERINGS (chapters 1-7)
2. errata & addenda for ALGEBRA (chapters 8-14)
3. errata & addenda for TOPOLOGY AND UNIFORMITY (chapters 15-21)
4. errata & addenda for TOPOLOGICAL VECTOR SPACES.(chapters 22-30) and the bibliography

In addition, the worst error was the ERROR IN THE INDEX: Now that the book has already been printed, I am horrified to discover that many of my index entries are off by a few pages. Here is a conversion table. In most cases,

      If the page number in  |  Then you should
      the index is between   |  increase that number by
      -----------------------+-------------------------
             1 and 430       |    0
           431 and 571       |    1
           572 and 673       |    2
           674 and 834       |    3

You may find it helpful to tape a copy of this table to the inside back cover of your book. Fortunately, most terms appear in boldface when they first occur in the text, so they're not hard to find.

Acknowledgments: So far, errors have been reported by [JI] John Isbell, [DJ] David Jennings, [MG] Michael Greinecker, [GL] Gérard Lang, [NM] Norm Megill, [PR] Paolo Roselli, [SS] San Skulrattanakulchai, [SS2] Satit Saejung, [RT] Rick Taylor, [JT] James Turner, and myself.