He was actively involved in organizing the "No-Tax" campaign at the Bardoli Satyagraha, the boycotting of the Simon Commission and appointed President of the Bombay Congress "War Council".

Imprisoned twice by British Indian authorities on charges of sedition for a total of three years, Alva was jail companion to Vallabhbhai Patel, Jayaprakash Narayan, Morarji Desai and J. C. Kumarappa.

In 1937, Alva married Violet Hari, a Gujarati Protestant from Ahmedabad and professor of English at St. Xavier's Indian Women's University College.

On 9 August 1943, the first anniversary of Quit India Day, Joachim and Violet Alva founded and debuted FORUM, a weekly news magazine which became known for its championing of the cause of independence.

An early advocate of planning, the public sector, nationalised banking and state control over major industries, he condemned France's napalm bombing of Indo-China and staunchly supported the Vietnamese cause.

In 1962, Alva led on India's attempts for closer ties with China, meeting Mao Zedong and Zhou Enlai in Beijing.

The couple were close associates of Khin Kyi, Burma's ambassador to India from 1960, widow of Burmese nationalist General Aung San.