The author analyses the question of social in-security both for the natives and the immigrants. His main thesis is that the problem has two faces: the one is the insecurity of native peoples, the other that of the immigrant. The cultural pluralism products by migrants which culture, religion and life styles are different from those of the native peoples generate a cultural relativism. The relativism of values, religions and life’s styles is the basis of ontological in-security. Strategies of action and images of the other are very strong intertwined. Native peoples and migrants have some time a positive image of the other, sometime a negative or a neutral one. Security policies request a dialogue between cultures and religions and must be founded on a positive image of the other.