The use of a model proposed by John Zaller shows that the process Of opinio
n formation in matters pertaining to foreign policy is similar to that obse
rved in related areas such as immigration and security us well as in specif
ically internal policy matters. The model is applied to the study of Swiss
electors surveyed at the time of federal referendum campaigns covering fift
een years. It is found that the level of support for the proposals is a fun
ction of the level of political consciousness and political predispositions
of the individual voter on the orle hand, and of the degree of disagreemen
t among the elites on the other. The formation of opinions on foreign polic
y matters finds its specificity in the conditions that characterize campaig
ns that differ in terms of intensity, level of conflict, and party alignmen
t.