The evaluation of skin irritation potential of chemicals is essential to secure the safety of individuals exposed to several substances designed for industrial, pharmaceutical or cosmetic use. Until recently, preclinical safety assessment of chemicals was largely based on animal experiments. Ethical concerns and the limited value of animal models in evaluating human skin irritation potential resulted in the development of alternative in vitro methods, such as EpiDerm, EPISKIN or SkinEthic, to assess irritation, i.e. cell cultures and human epidermis models. International organizations like the European Centre for the Validation of Alternative Methods (ECVAM) promotes and monitors the development of nonanimal tests. Human patch tests and use tests also provide an opportunity to identify substances with significant skin irritation potential without recourse to the use of animals. These tests are useful to assess skin irritation potential of cosmetics and detergents.