The Social Christian Unity Party (Partido de Unidad Socialcristiana) is a centre-right political party in Costa Rica.PUSC considers itself a Christian democratic party and, as such, is a member of the Christian Democrat Organization of America (ODCA). It was founded in 1983 by merger of the parties that were part of the Unity Coalition: the Christian Democratic, the Republican Calderonist, the Popular Union and the Democratic Renewal Party. Its historical roots are in Calderonism, i.e.