This thesis explores two topics in International Migration: the impact of immigration on the labor market; and attitudes of natives towards immigration. Essays one and two explore two mechanisms that could explain the imperfect substitutability between migrant and native workers which explain why immigration has a small impact on natives' wages. The third essay studies how exposure to immigrants influences the attitudes of natives towards immigration. The three essays take advantage of the setting in Switzerland, which has a high share of immigrants and notably migrants from neighbouring countries that share a common language with Switzerland. The third essay also takes advantage of the Swiss direct democratic system, which allows any population group to propose a change in the Constitution.