This course will focus on various aspects of individual bilingualism and multilingualism. It will aim to demonstrate that a bilingual is more than just the sum of two monolinguals and that bi-/multilingualism is a lifetime experience. During the course we will look at the different contexts of bi-/multilingualism and examine different bilingual populations, for example migrants and refugees, heritage language speakers, bidialectal speakers and new speakers of minority languages. We will discuss individual differences between bilinguals and explore how different extralinguistic factors, such as the age of second language acquisition, may affect bilingual outcomes. We will examine the relationship and interaction between the different languages in the bilingual mind and look into how bilingualism affects the acquisition of subsequent languages. Mental organization of the two languages and bilingual online linguistic processing will be also discussed. Moreover, we will outline some cognitive advantages of bilingualism and examine how bilingualism re-wires the brain. Finally, we will examine the issue of language and thought to see how bilinguals think and perceive the world.The course will be co-taught by instructors from Adam Mickiewicz University and Aristotle University of Thessaloniki. The course will rely on materials produced as part of the TEAM project, including pre-recorded interviews with established bilingualism researchers from all over the world. The TEAM project is a Strategic Partnership of 9 universities from Poland, Greece, Italy, Croatia, Spain, Germany, Israel and the United Kingdom. All the partners are also members of the Bilingualism Matters international network.