The Health Insurance Development for the Informal Workers and Their Families The objectives of this research are two fold. The first objective is to examine the health care situation and health care among the informal workers and their families. The second objective is to develop a proposed guideline for health insurance plans for the informal workers and their families.The study reveals that informal workers and their families still lack preventive health care and maintenance health care. The majority of them do not have health insurance and have to pay for medical care at their own expense, especially for costly severe illnesses and injuries. However, their family members who are elderly and children are covered under the Free Medical Cards. For these reasons, there should be health insurance plans for the underprivileged especially the informal workers and their families. They should be guaranteed health care in accordance with the Human Rights Act and the Thai Constitution of 1997, stating that all citizens are entitled to quality health care, both preventive and maintenance health care. Thus, health insurance plans provided must contain reliable long-term programs with competent and effective management. In order to achieve effective health insurance management, four components are required namely a policy component, a fund management component, a health care network component, and a quality assurance component. There must be a network of health care services for the people. The network should insure cooperation among the government, the private sector, the business sector and the people’s organizations. Tax revenues must be allocated to provide basic health care services for illness, child delivery, disability, annual physical examination, and health information for informal workers. Program monitoring mechanisms are needed to ensure quality health care, a high standard of services, and effective fund management. These mechanism should consist of both internal and external examiners. Informal workers should participate in the program, especially in preventive health care, and ensure their rights to health care services. In addition to the components mentioned above, effective health insurance management requires supportive laws, development of an information network, ongoing public relations programs, development of an appropriate taxation system, and establishment of organizations for informal workers. The following suggestions are herein proposed :Informal workers and their families should be encouraged to gain competence in preventive health care and during the time of illness or injury.The organizations concerned should take responsibility in solving health care problems for informal workers.Informal workers and their families should be encouraged to organize themselves and to form health care networks.The government must provide quality health insurance plans for informal workers and their families on the basis of equal rights.Health insurance management should emphasize the development and improvement of existing organizations rather than the establishment of new organizations unneccessarily.Health insurance plans should provide alternative programs.A health care database for informal workers and their families should be developed.