Discrimination (Employment and Occupation) Convention (ILO Convention No. 111) Article 1 (a)
Article 1
1. For the purpose of this Convention the term "discrimination" includes:
(a) Any distinction, exclusion or preference made on the basis of race, colour, sex, religion, political opinion, national extraction or social origin, which has the effect of nullifying or impairing equality of opportunity or treatment in employment or occupation.