From 1946 to 1948, Indians in South Africa engaged in the Passive Resistance campaign against apartheid. Meer, who joined the campaign, established the Student Passive Resistance Committee, where she embarked on a career as an anti-apartheid campaigner. She helped establish the Durban districts Women's League to build alliances between Africans and Indians, after the race riots that occurred between the two groups in 1949. The organisation built a creche, distributed milk and fought the arrests of African women with passes.
When the National Party came to power in 1948, imposing the policy of apartheid, Meer's involvement increased and she spoke publicly against apartheid. Her activities led to her banning in 1952, which excluded her from all public gatherings and from being published. She became a founding member of the Federation of South African Women (FEDSAW) that spearheaded the historical women's march to the Union Buildings that occurred on the 9th of August 1956.
During the 1960s, when the majority of activists were being detained without trial, she organised night vigils and in the 1970s when the Black Consciousness Movement was starting to dominate, she was again banned and was subsequently detained for trying to organise a rally with Steve Biko. Shortly after her release in 1976, Meer survived an assassination attempt, when her house was petrol bombed.
From the 1980s to the 1990s, Meer worked with NGOs, fighting for the rights of shack-dwellers and rural migrants. She headed the Natal Education Trust, which built schools in Umlazi, Port Shepstone and Inanda; established the Tembalihle Tutorial