Secret societies may be considered a danger to their community or nation. Secrecy may be partial or complete. Partial secrecy may take the form of a secret initiation ceremony while public acknowledgement is made of general objectives. Many secret societies are hierarchical. Secret societies may be mystical, occult, heretical, revolutionary, perverse, violent, subversive, criminal or primitive. Political secret societies may only be so constituted by the fact of their having held a number of meetings to affect some particular purpose. During a regime or governmental administration, they may be an inner circle of people wielding the power 'behind the throne' or they may be the manipulators of political parties, operating as a cabal.
Famous secret societies include the Pythagorean Brotherhood, the Carbonari, the Illuminati, the Order of Assassins, the Jesuits, the Chinese Tongs, the Black Hand, the Weathermen, and the Black September group among many others.
Secret organizations that do intelligence or police work, may sometimes breed secret societies within themselves. For example, Brownshirt Nazis, partly secret enforcers, had under them the Blackshirt SS, which controlled the Gestapo, the secret police. Large urban police departments may be controlled by an inner circle of officers, or by an official benevolent or fraternal organization. In the UK for example, objection was made to Freemasonry among policemen. In the Vatican, protected by the same secret environment as afforded to the Curia, a criminal conspiracy manipulating the Vatican bank's prestige was recently fostered and investigation was impeded by Vatican secretiveness.