Occupational hazards as well as occupational injuries and diseases are frequent and serious problems not only in industrialized high-income countries, but also in low- and middle-income countries (LMICs). In high-income countries, the occurrence of occupational injuries and chemically-related disorders has decreased while psychosocial problems and issues for disabled, aging, and other vulnerable workers have increased. In the LMICs, “traditional” occupational hazards and related injuries and diseases are still a major concern. Globalization, while providing some benefits to workers, has presented many negative effects, such as transfer of hazardous technologies and substances to LMICs, widening of income gaps, and worsening of working conditions and worker income, especially for agricultural workers, those with little education, and informal workers. The chapter provides a global overview of work and workers as well occupational health and safety hazards and related challenges.