The delegitimization of the traditional political parties in Colombia and Paraguay is a journey through theories and perceptions about the responsibility of political representation that electors and elected officials share. Throughout a study of political history and political parties in two apparently different systems such as the Colombian consociational system, during the “Frente Nacional”, and the Paraguayan bipartisanship during the Stroessner dictatorship the institutional decay is portayed resulting in the growing disillusionment of citizens, and the subsequent emergence of new political forces and the lag of traditional ones.