Lobbying (also lobby) is the act of attempting to influence decisions made by officials in a government, most often legislators or members of regulatory agencies. Lobbying is done by many types of people, associations and organized groups, including individuals in the private sector, corporations, fellow legislators or government officials, or advocacy groups (interest groups). Lobbyists may be among a legislator's constituencies, meaning a voter or block of voters within his or her electoral district, or not; they may engage in lobbying as a business, or not. Professional lobbyists are people whose business is trying to influence legislation on behalf of a group or individual who hires them. Individuals and nonprofit organizations can also lobby as an act of volunteering or as a small part of their normal job (for instance, a CEO meeting with a representative about a project important to his/her company, or an activist meeting with his/her legislator in an unpaid capacity). Governments often define and regulate organized group lobbying that has become influential.