The second edition of Volume B was published in April, 2001. Several authors indicated to the editor the need of revision of their contributions, and other updating suggested itself. New authors were invited in this connection. These are: Dr. L. Tong, Dr. J. C. H. Spence, Dr. Michiyoshi Tanaka, Dr. Pawel A. Penczek, Dr. Lachlan M. D. Cranswick, Dr. Thomas Darden and Dr. Hans Boysen. We summarize below the status of the changes and new additions to be incorporated in the third edition of Volume B:

• Chapter 1.5 was extensively revised by its authors, Dr. H. Wondratschek and Dr. M. I. Aroyo.
• Corrections and minor revisions were introduced in Chapters 1.1 and 2.1 by Dr. U. Shmueli.
• Chapter 1.2: 'The Structure Factor' was corrected and revised by its author, Dr. P. Coppens.
• Chapter 2.2: 'Direct methods' was revised and extensively updated by its author, Dr. C. Giacovazzo, with particular attention to applications to macromolecular crystallography.
• Chapter 2.3: 'Patterson and molecular replacement techniques' was revised and updated by its authors, Drs M. G. Rossmann and E. Arnold, and their newly invited colleague Dr. L. Tong.
• Chapter 2.5: 'Electron diffraction and microscopy in structure determination'

• Section 2.5.1, Foreword to Chapter 2.5 by the late Dr. J. M. Cowley, was updated and revised by Dr. J. C. H. Spence.
• Section 2.5.2 on electron diffraction and microscopy by the late Dr. J. M. Cowley will probably remain unchanged. Readers' questions on this section may be addressed to Dr. J. C. H. Spence.
• Section 2.5.3: 'Space-group determination by convergent-beam electron diffraction', by the late Dr. P. Goodman, was now completely rewritten by Dr. M. Tanaka and is entitled: 'Point-group and space-group determination by convergent-beam electron diffraction'.
• Section 2.5.4 on electron diffraction structure analysis (EDSA) by the late Dr. B. K. Vainshtein and the late Dr. B. B. Zvyagin, will probably remain unchanged. Readers' questions on this section may be addressed to Dr. D. L. Dorset.
• Section 2.5.5 on image reconstruction (by electron microscopy), by the late Dr. B. K. Vainshtein, will remain unchanged. Readers' questions on this section may be addressed to Dr. Pawel A. Penczek.
• Section 2.5.6 on three-dimensional reconstruction (by electron microscopy), by the late Dr. B. K. Vainshtein, was updated and expanded by Dr. Pawel A. Penczek.
• A new Section 2.5.7 on current approaches to single particle reconstruction (by electron microscopy) was written by Dr. Pawel A. Penczek.
• The section on direct methods in electron crystallography, by Dr. D. L. Dorset, labeled as 2.5.7 in the second edition of Volume B, will now become Section 2.5.8 in the third edition.
• Chapter 3.3 on molecular modeling and graphics, by Dr. R. Diamond, was updated, and was extended by a section on implementations of molecular graphics to small and medium-sized molecules. Dr. Lachlan M. D. Cranswick contributed this extension.
• Chapter 3.4 on convergence acceleration techniques of lattice sums, by the late Dr. Donald E. Williams, will remain unchanged. Readers' questions on this chapter may be addressed to Dr. W. Smith of the Daresbury Laboratory.
• Dr. Thomas Darden wrote Chapter 3.5 on extensions of Ewald methods. This chapter deals with Ewald sums within and beyond the point-charge model, and with the use of Fast Fourier Transform in efficient computation of lattice sums. An impressive numerical comparison concludes the chapter.
• Chapter 4.1: 'Thermal diffuse scattering of X-rays and neutrons' by Dr. B. T. M. Willis was corrected and updated.
• Chapter 4.2: 'Disorder diffuse scattering of X-rays and neutrons' was revised and updated by its authors Drs. F. Frey and H. Jagodzinski, and their newly invited colleague, Dr. H. Boysen.
• A minor correction in Chapter 4.6: 'Reciprocal space images of aperiodic crystals' was introduced by Dr. W. Steurer
• Chapter 5.1: 'Dynamical theory of X-ray diffraction' was updated and corrected by its author, Dr. A. Authier.

All the contributions are in the hands of the Technical Editor in Chester, who is presently busy with the technical editing of the third edition of Volume B. The target date for the publication of the third edition of Volume B is end 2007 or early 2008.

Updated 27 June, 2007.