Globally increasing numbers of older people bring both challenges and opportunities for old age psychiatry services. This chapter outlines the history, underlying principles, and policy context for contemporary mental health services for older people. It discusses components of services, including community health teams, memory assessment services, consultation-liaison psychiatry, and in-patient mental health care, as well as newer types of service, such as crisis teams and outreach to care homes. Other recent developments include various models of case management and emphasis on post-diagnostic support. Equally important are issues of equality and access, and the chapter covers several key areas, such as age, gender, sexual orientation, religion and spirituality, and rurality. Major challenges to old age psychiatry come from limited resources and non-recognition of the distinct needs of older adults, as well as the demands of the growing older population, advances in science and technology, and the need to attract talented psychiatrists into this field.