The global nitrogen cycle is the one most impacted by mankind. The past decade has changed our view on many aspects of the microbial biogeochemical cycles, including the global nitrogen cycle, which is mainly due to tremendous advances in methods, techniques and approaches. Many novel processes and the molecular inventory and organisms that facilitate them have been discovered only within the last 5 to 10 years, and the process is in progress. Research on Nitrification and Related Processes, Part B provides state-of-the-art updates on methods and protocols dealing with the detection, isolation and characterization of macromolecules and their hosting organisms that facilitate nitrification and related processes in the nitrogen cycle as well as the challenges of doing so in very diverse environments.