This introduction article discusses language vitality and language diversity in connection with linguistic well-being, which were the main ideas reflected behind the theme of the AFinLA Autumn Symposium 2018, “Keeping languages alive”. Linguistic well-being is a new concept that addresses the issues related to language policy and linguistic practices within a speech community and how these impact the individual members of that community. Among the main factors behind linguistic well-being we find linguistic human rights, which emphasize, for example, the right for anyone to identify with one or more languages without being discriminated and the right for basic education in one’s own language. These rights are particularly linked to how endangered and minority languages are treated in the society and they can be actively promoted by language policy and education. However, linguistic well- being is not just a matter of minorities but it affects the whole community. The more diverse the language environment and linguistic landscape of a speech community is, the healthier and more affluent the whole community is – both its minority and majority language speakers.