Public consultation, or simply consultation, is a regulatory process by which the public's input on matters affecting them is sought. Its main goals are in improving the efficiency, transparency and public involvement in large-scale projects or laws and policies. It usually involves notification (to publicise the matter to be consulted on), consultation (a two-way flow of information and opinion exchange) as well as participation (involving interest groups in the drafting of policy or legislation). A frequently used tool for understanding different levels of community participation in consultation is known as Arnstein's ladder.