Mental, physical, and social health are closely interwoven and interdependent. Recent research and better understanding of the relationships between mental, physical, and social health indicate that each is crucial to the overall well-being of individuals, societies, and countries. Because mental health and mental disorders have been ignored or neglected in many parts of the world, the reciprocal impacts between physical health and mental health are not readily apparent. Providing treatment in primary care would enable the largest number of people to get easier and faster access to services. Current health personnel should be trained in the essential skills of mental health care, and mental health should be included in health training curricula.