Primary prevention refers to activities directed to high-risk groups, within a community not yet labeled as psychiatrically ill. These activities have the purpose of preventing the onset of emotional disturbance and enhancing the level of mental health. In general, whatever contributes to human stress in a community so that the individual or group is unable to cope can lead to poor psychological health and physical disorders and must be eliminated or reduced if health is to be promoted. The strategies for achieving the goals of primary prevention are two-fold: (1) strengthening individual competencies and/or descreasing individual vulnerabilities; and (2) promoting and strengthening community competencies and resources to modify or eliminate environmental and social stress. Groups frequently at risk in developing nations are women, migrants, and urban dwellers in a society undergoing industrialization. Their problems include illiteracy, lack of occupational skills, isolation, and inexperience with city life, problems which can cause a host of health problems. Prevention programs should be primarily educational and based on assessed needs of the targeted group. Planners need to seek the interest and cooperation of various community agencies for collaboration on formulating objectives, designing health promotion activities, and funding and implementing programs. Prevention programs are more likely to be successful when practitioners pool their resources with public as well as nongovernment organizations. (JB)