The HIV/AIDS epidemic is now a global crisis, and constitutes one of the most formidable challenges to development and social progress. In the most affected countries, the epidemic is eroding decades of development gains, undermining economies, threatening security and destabilizing societies. In sub-Saharan Africa, where the epidemic has already had a devastating impact, the crisis has created a state of emergency. Beyond the suffering it imposes on individuals and their families, the epidemic is profoundly affecting the social and economic fabric of societies. HIV/AIDS is a major threat to the world of work: it is affecting the most productive segment of the labour force and reducing earnings, and it is imposing huge costs on enterprises in all sectors through declining productivity, increasing labour costs and loss of skills and experience. In addition, HIV/AIDS is affecting fundamental rights at work, particularly with respect to discrimination and stigmatization aimed at workers and people living with and affected by HIV/AIDS. The epidemic and its impact strike hardest at vulnerable groups including women and children, thereby increasing existing gender inequalities and exacerbating the problem of child labour.