New England Role Playing Organization
NERO is an acronym for New England Role playing Organization. It is the name of a two fantasy LARPs, which were once one but split. These can be disambiguated by referring to them as NERO Alliance and NERO International.
NERO International was the original organization, and was founded in 1988 by Ford Ivey. Michael Ventrella, one of the founders of NERO with Ford, formed the splinter group the NERO Alliance 1998. Both have chapters across North America, with thousands of players.