A lawyer is a person who practices law, as an attorney, counselor or solicitor. Law is the system of rules of conduct established by the sovereign government of a society to correct wrongs, maintain the stability of political and social authority, and deliver justice. Working as a lawyer involves the practical application of abstract legal theories and knowledge to solve specific individualized problems, or to advance the interests of those who hire lawyers to perform legal services. The role of the lawyer varies significantly across legal jurisdictions, and so it can be treated here in only the most general terms.