Bacterial single-strand DNA-binding protein (SSB) interacts with many proteins involved in the diverse process of genome maintenance. The interactions are mediated by the essential and conserved amphipathic C-terminus (SSB-Ct). SSB plays a critical role in localizing and stimulating the activity of a wide variety of DNA-processing proteins. The interaction partners have been identified and studied using a variety of methods, one of which, ammonium sulfate co-precipitation, is described here.