All individuals have to deal with health and illness. Their health behavior can directly impact their health outcomes. Engaging in healthy behaviors reduces the risk of certain conditions, while unhealthy behaviors can increase that risk. Health behaviors encompass overt behavioral patterns, actions, and habits that relate to maintaining, restoring, and improving health (Gochman, 1997: 3). This definition includes various behaviors such as diet, alcohol use, smoking, physical activity, sexual behaviors, medication adherence, screening, and vaccination. Examining health behaviors in both healthy and health-compromised populations is a crucial area where public health has made significant contributions to improving people's well-being.

Health literacy is closely related to health behavior and refers to a complex network of knowledge and skills that empower individuals to educate themselves and be educated (Nutbeam, 2008; Sørensen et al., 2012). Nutbeam (2008: 2072) defines health literacy as "the extent to which individuals have the capacity to access, process, and understand basic health information and services needed to make appropriate health decisions." Individuals with limited health literacy often struggle to navigate the healthcare system, especially when it comes to accessing preventive care, screenings, diagnoses, and treatments. McCaffery et al. (2010) argue that low health literacy occurs when a person's literacy and numeracy skills do not align with the often technical, complex, and unfamiliar information provided by healthcare professionals and organizations.

To improve people's health behavior, health promotion is necessary. Health promotion is the process by which individuals increase control over and enhance their health (WHO, 1986). Numerous health promotion programs and interventions have been developed to improve the health and well-being of individuals and groups. These interventions aim to shift the focus of healthcarefrom hospitals to community-based settings (Baxter et al., 2018).

This Handbook consolidates essential knowledge on health behavior, health literacy, health education, health promotion, and programs/interventions that can enhance global health. It is divided into three books and several parts covering health disciplines, theories, concepts in health behavior, health promotion, and illness prevention. Book one will contain specific sections that address health-related concepts and health behavior. Book two will embrace theoretical and practical aspects of health promotion, health literacy and health programs and interventions for promoting health. Book three will comprise health behavior and health promotion related disciplines, environment and health behavior, and research methods applicable to examining health behavior and illness prevention in individuals and groups. Chapters in three books encompass both theoretical and practical aspects of health behavior and illness prevention.

The Handbook takes a critical perspective when addressing these issues and avoids adopting a deficit model or victim-blaming approach. For instance, health-compromising behavior may stem from low health literacy, which could, in turn, result from a lack of education. However, the Handbook seeks to delve into the underlying causes of individuals' lack of education, which may be linked to marginalization, poverty, power imbalances, and similar factors. By avoiding a deficit model or victim-blaming approach, the chapters in the Handbook will tackle the root causes of health-compromising behavior.

Contributors to the Handbook include researchers, educators and practitioners specializing in health behavior and health promotion. Their work contributes to illness prevention and the improvement of health and well-being in individuals and groups. The chapters will be valuable to students, researchers, and practitioners in the health fields.

Professor Pranee Liamputtong is a distinguished medical anthropologist whose research focuses on the health and well-being of women, children, immigrants, refugees, the elderly, ethnic minorities, and transgender individuals. Her work is particularly dedicated to maternal and neonatal health, sexual and reproductive health, gender and sexual well-being, psychological health, and chronic illnesses influenced by climate change. Her recent studies have examined gender and sexual health concerns among Asian women, refugee and immigrant women, youth, and transgender women from ethnic minority backgrounds. In Vietnam, she has investigated the effects of air pollution on maternal and neonatal health. Additionally, her research explores the health and overall well-being of ethnic minority women. As a leading social science researcher, Professor Pranee has authored numerous books on qualitative research methodologies and various social and health-related topics. Her books include Qualitative Research Methods, Research Methods and Evidence-Based Practice, Handbook of Qualitative Cross-Cultural Research, Researching the Vulnerable, Handbook of Research Sensitive Research in the Social Sciences, Social Determinants of Health, Focus Group Methodology, Research Methods in Health Social Sciences, Handbook of Social Sciences and Global Public Health. These works are widely recognized and used in both Australia and internationally. Before joining VinUni, Professor Pranee served as a Professor of Public Health, where she taught Qualitative research methods, Social determinants of health, Gender and health, Cultural diversity in healthcare, and Health communication. At VinUniversity, she has contributed to both medical and nursing degree programs, teaching courses such as Health Communication, Health Promotion and Disease Prevention, Research Methods in Nursing, and Qualitative Research Methods in the medical program. She has also mentored numerous undergraduate students in the MD and BN programs, guiding them through research projects as part of their studies and career development. Additionally, she has provided mentorship to faculty members in their research and publication efforts. Currently, Professor Pranee serves as Professor of Social Science and Chair of the Research Committee within CAS as well as Leader of the Living Lab pillar at the Center for Environmental Intelligence (CEI).