The impact of migration is a key element to understand the history of humanity. Displacement, both individually and in groups, has been decisive in the survival of human beings. However, in recent times words such as "immigrant" or "refugee" have often been problematized. The migration process is a complex phenomenon with challenges for individuals and communities. With more than thirty years of experience in clinical and psychosocial care for immigrants and refugees, the psychiatrist Joseba Achotegui answers these and more questions, while developing in depth the renowned theory of the seven duels of migration that he formulated in 1995: family and loved ones, language, culture, land, social status, belonging group and physical risks, factors that are analyzed from the perspective of the immigrant and the native, to understand what affects the processes of migration, interculturality and mental health.