Under art 3 of the International Convention on the Elimination of All Forms of Racial Discrimination (‘ICERD’), states parties particularly condemn racial segregation and apartheid and undertake to prevent, prohibit and eradicate all practices of this nature in territories under their jurisdiction. The provision is central to Palestine’s inter-state communication against Israel under arts 11–13 of ICERD, in which it is argued that Israel’s policies and practices in the occupied Palestinian territories constitute apartheid. Importantly, Palestine invokes two obligations inherent in art 3 — the individual obligation of Israel to prevent, prohibit and eradicate all practices of this nature, and the collective obligation of all states parties to ICERD to condemn such practices by not recognising as lawful the illegal situation, or rendering aid or assistance in its maintenance. This article examines the origin, meaning and implications of the collective obligation to condemn apartheid under art 3 of ICERD. It traces its emergence in the text of art 3 through the drafting history of the provision. It outlines its implementation by the Committee on the Elimination of Racial Discrimination (‘CERD’) in relation to apartheid South Africa from 1970–94, a period in which South Africa remained outside the treaty and the obligation of all states parties to condemn apartheid was the focus of the Committee’s work. Finally, it considers its potential implications in Palestine v Israel, underlining that a finding of apartheid would render the obligation opposable in relation to the other 180 states parties to ICERD under all of its mechanisms. It could be monitored in state reports, individual communications or inter-state communications before CERD, or litigated in inter-state proceedings before the International Court of Justice.