This chapter investigates discourses of mental health in the British parliament over two centuries (1800–2020). A pattern-driven approach is used to explore terminology related to mentally ill people, mental institutions, and mental health in general. The study focuses on lexical trends in parliamentary discourse, the extent to which mental health discourse was discussed in general, and the way in which the lexis of modern mental health care has developed. The results show that the major shifts in the entire lexical field have happened in specific time periods, the turning points being in the 1840s, 1930s and 1950s. The general attitude also seems to have shifted, and the data show an increasing concern for legally protecting people with mental illness.