The definitive reference on protein modules covers all relevant modular domains mediating protein-protein interactions:

- SH2, SH3, WW domains
- EVH1 and GYF domains
- PTB and FHA domains
- Protein kinase domains
- SET, Bromo and Chromo domains
- PDZ and EH domains
- Ubiquitin- and actin-binding domains
- Phosphoinositide-binding domains

Structure, function and interaction partners of the domains are systematically treated, a general section covers methods to study protein-protein interactions on a proteome-wide scale.