Significant progress has been made in the theoretical modelling of scanning
probe microscopy. The models available now are sufficiently refined to pro
vide information not only about the surface, but also the probe tip, and th
e physical changes occurring during the scanning process. This has signific
antly improved the quantitative analysis of experimental and theoretical re
sults. Scanning probe microscopes can now be reliably used to analyse event
s on the level of single atoms and single electrons. (C) 2001 Elsevier Scie
nce Ltd. All rights reserved.