Three themes underlie the topics in this chapter. Physical, psychological, and social problems often occur together, linked by chance or causality in the life of the old person. Very rarely can one problem be dealt with in isolation, and many different sources of expertise may be engaged with a single individual. Therefore good coordination between different agents is essential in old age psychiatry, both for the individual patient and in the overall planning of services. Many of the pathologies characteristic of old age are gradual in onset and degenerative in nature, and more due to failures in processes of repair than to an ‘external foe’, so the distinction between disease and health is often quantitative rather than qualitative. ‘Normality’ becomes a social construct with fluid borderlines, containing the overlapping (but not identical) concepts of ‘statistically common’ and ‘functionally intact’. Thus the popular perception of normal old age includes the ‘statistically common’ facts of dependence and failing function, whereas ‘intactness’ (excellent health and vigorous social participation) is seen as remarkable rather than the norm. But the boundaries of ‘old age’ are also socially constructed—in developed countries good health at the age of 65 would nowadays be regarded as a normal middle-aged experience, whereas superb health at 95 would still be something noteworthy. Since some degree of physical dependence, forgetfulness, and vulnerability to social exclusion is expected in old age, meeting those needs is also regarded as a ‘normal’ demand on families and community agencies such as social services, rather than the responsibility of health care providers. As the severity of the needs increases, however, so also does the perceived role of health professionals, both as direct service providers and in support of other agencies. Because of the high prevalence of cognitive impairment in old age (especially among the ‘older old’), questions frequently arise as to the competence of patients to make decisions. Older people who cannot manage decisions alone may come to depend increasingly on others for help; or, resisting dependence, they become vulnerable through neglect of themselves or through the injudicious decisions they make. When an incompetent person is cared for by a spouse or family member, the danger of self-neglect or of ill-considered decisions is lessened, but instead, there are the risks of faulty decisions by the caregiver (whether through ignorance or malice), and also risks to the health of the caregiver from the burden of dependence by the incompetent person. Legal mechanisms, differing from one country to another, exist to safeguard the interests of incompetent people. These three themes will be developed further, and with them the following special topics: 1 multiple problems: including sleep disorders in old age, medication in old age psychiatry, and psychological treatments in old age psychiatry; 2 blurred boundaries of normality: including the role of specialist services and support between agencies; 3 incapacity and dependence: including balancing the needs of patients and caregivers, abuse of older people, ethical issues, and medico-legal arrangements for safeguarding decisions.