In doing his research Gordon Hall would create surveillance files for many extremist groups and extremist group members. He would attend protests, follow people to meetings, attend group meetings and keep detailed notes of his work. This post contains some examples of documents created by Gordon Hall from the 1960s. Many extremist groups would act in secrecy and Gordon Hall went to great lengths to learn more about their inner workings. Some may find Gordon Hall’s actions here extreme and maybe even inappropriate, but it seems that he felt he had to do this in order to learn more about extremism to help inform his work in exposing and describing extremist groups to the public.