What do you do if you want to escape from the bottom of the social heap?
Thousands of Dalits - people from the lowest Hindu caste - have recently taken part in a mass conversion ceremony in central India.
Thousands more celebrated the 50th anniversary of the conversion to Buddhism of one of the founders of modern India, Bhimrao Ambedkar.
Dr Ambedkar was a Dalit himself.
He believed the only way for Dalits to escape from their low status in the rigid caste system was to reject Hinduism and convert to Buddhism.
He also argued that they should stand up for their rights, move to the cities and seek education.
Traditionally, Dalits could only aspire to being landless farm workers, day labourers or rubbish collectors.
But Dr Ambedkar's movement, now millions strong, is not altogether popular.
Some Dalits have had to pay a high price for following Dr Ambedkar's teachings.
Dan Isaacs examines the difference conversion has made to those who have followed Dr Ambedkar's path.
Have they been able to truly escape from the caste system?
Crossing Continents was broadcast on Thursday, 28 December 2006 and repeated on Monday, 1 January at 2030 GMT.
Presenter: Dan Isaacs
Producer: Tessa Watts
Editor: Sue Ellis