The Security Department comprises the Director of Security, the Serjeant-at-Arms and the Deputy Serjeant-at-Arms. The Director is responsible for the security of and order in the House. He is assisted by the two Serjeant-at-Arms and a complement of CISCO guards.

In addition to assisting in the security and maintenance of order in the House, the two Serjeants-at-Arms also undertake the House's ceremonial functions. One ceremonial function is the procession comprising the Speaker, the Clerk of Parliament, the Assistant Clerk and the Serjeant-at-Arms at each sitting of Parliament. The Serjeant will lead the procession into the Chamber bearing the mace which is the symbol of the Speaker's authority.

In maintaining order the Serjeants are empowered to arrest persons who have committed breaches of privileges of the House.