Lag in political attitudes and legislation with respect to the demands of economic and technological or social change reflects the unwillingness of certain powerful groups with a vested interest in the status quo to change or to relinquish current benefits. It may also be a function of an outmoded or cumbersome political structure or of inadequate traditionalist opinions. It produces a barrier to economic, social and political progress and serves to maintain existing inequalities and injustices, ranging from poverty to pollution. Political lag can occur on either the national or the international level.