The International Labour Organization has marked World Day for Safety and Health at Work every April 28 since 2003, building on a tradition launched by trade unions in 1996 known as "Workers' Memorial Day," honoring victims of workplace accidents and occupational diseases. The date coincides with the day of mourning observed by labor movements in many countries. The day promotes the prevention of occupational accidents and diseases worldwide by raising awareness of the importance of safe working environments that protect workers' physical and mental health. ILO estimates suggest millions of workers suffer work-related injuries or illnesses each year, some fatal, making the promotion of a culture of prevention and safety both an economic and a social priority. Governments, employers' organizations, and trade unions worldwide mark the day with workplace awareness campaigns, seminars on occupational safety best practices, and recognition of companies that adopt high health and safety standards.