Migration aspirations lie at the heart of self-selection into migration. In this paper, we study three questions: How do individual, household, origin-country, and destination-country characteristics interact? What factors are most influential? Who wants to leave in what context? We develop a new stylized model which integrates insights from the recently established aspirations-capabilities framework into standard utility maximization. We jointly investigate destination country factors (income and legal status), journey factors (costs and risks involved), and origin country factors (income, economic trends, and quality of public goods) using a conjoint choice experiment with 2708 participants in Uganda and Senegal. Our results show that all these dimensions significantly affect migration decision-making. However, the most important dimensions are the legal status and the risk of dying on the journey. Legal migration opportunities are even more influential for individuals that are content with their income situation at home. In line with the aspirations-capabilities framework, we show that higher life aspirations come with a higher willingness to migrate.