US aid interventions have greatly advantaged some countries in their quest for development, but not others. The extensive development assistance, technology transfers and market access that the United States government granted Taiwan and South Korea in their development and the aid recently given Costa Rica were important factors in their development successes. On the other hand, the inappropriate policies of the US in Vietnam in the fifties, El Salvador in the eighties and Nicaragua in the nineties, programmed these interventions to economic as well as political failure.