The first part of the thesis evaluates policy change effected toward the Old Age and Survivors Insurance (OASI) program and the Food Stamp program in the United States during the Reagan years; and the Retirement Pensions program and Social Assistance in the United Kingdom during the Thatcher years (1979-1988). The Reagan administration was largely unsuccessful in attaining its major goals toward reforming OASI. Greater success was forthcoming in its efforts to effect policy change toward the Food Stamp program. Reagan, failed, however, to transfer authority for the welfare function over to the states. Non-incremental policy change was effected toward the Retirement Pensions program during the Thatcher years. A radical redirection in social policy toward the unemployed was also forthcoming. The argument is advanced that the social policies of the two administrations were guided by a determination to reinforce the historical distinction between the deserving and undeserving poor. The second part of the thesis assesses how the attempts of the two administrations to reform the welfare state were constrained by public opinion and the legislative branch of government. The public popularity of OASI severely constricted the reform options available to the Reagan administration. A broad relationship existed between public opinion on nutritional issues and policy output with relationship to the Food Stamp program. The administration's attempts to reform the welfare state were constrained by the complex legislative structure of U.S. government, and by divided partisan control of Congress. Strong British public support for the welfare of the elderly inhibited the government from attempting to cut basic retirement pension benefits. Public opinion exerted a minimal degree of influence on the direction of Social Assistance reform. Thatcher's success in effecting non-incremental reform was facilitated by the structural design of Parliament. Her position was fortified by large cohesive Conservative party majorities in the House of Commons. Policy change in Britain during the Thatcher years is interpreted on a theoretical level through an adversarial model of the policy making process. A consensus model is utilized to facilitate understanding of Reagan's experiences in office.