Soliciting votes or other support for one's cause from decision makers especially legislators through interviews, letter writing and other forms of communication.
Interest groups influence legislation by contributions to candidates running for public office, communications to legislators and constituents, payment of retainers, promotion of mass demonstrations, withdrawal of financial aid, and threats of physical violence.
Most people would regard such lobbying as a legitimate and basic right in any democracy. Politicians need to be aware of the needs (and wants) of various sectors of the community and to be exposed to a range of policy ideas.
Lobbying by well-financed and organized pressure groups can circumvent prevailing public opinion. Law-makers are forced to legislate on the basis of the loudest voices and financial incentives. It undermines the democratic legislative process by going outside the formalized system.