Groups who say they face discrimination within their religions because of their ranking in society are gathering for a conference in London on the theme of "untouchability". But is the caste system still used as means of excluding people within some religious groups in Britain?
Caste consciousness is a feature of life for many Hindus and Sikhs
The first world conference on "untouchability" aims to draw together the experiences of people from as far afield as Nigeria, Britain, and Japan.
Such "untouchability" or social exclusion, based on membership of certain groups, is a continuing problem for sections of the population worldwide, say the conference organisers.
One of the most well-known forms is the caste system which is practised in the Indian sub-continent, but activists claim similar ways of organising people into higher and lower groups in society can be found throughout the world.
They say that up to 250 million people are affected by the issue, and children of immigrants who settle in different parts of the world are not immune.
Reena Jaisiah is a 29-year-old teacher and arts director from Coventry.
She was raised by parents from a Punjabi background who were not particularly religious, but were from the Dalit community, a group of people who are considered to be ritually unclean by Hindus.
In India, Dalits are often forced to take the worst kinds of jobs, and can live their lives in poverty because of a system that gives religious sanction to discrimination.
Reena's parents rejected the caste system, but did not tell her about her background - which led to questions from schoolmates and ultimately, bullying when they discovered that she was a Dalit.
"People with a strong religious feeling always want to know what caste you are", she says.
"My parents encouraged me to conceal my background, but I felt inferior to children from other castes."
Reena also encountered prejudice while at university and says she can still see the caste system at work today amongst Hindu schoolchildren, with pupils exhibiting a form of "caste consciousness" by treating others according to their perceived place in society.
The Indian government made caste discrimination unlawful in 1976, though it is still practised in some areas.
So why is the problem continuing, and will any Indian reform affect British communities?
Babu Gogineni is from the International Humanist and Ethical Association, one of the conference organisers.
He believes that political reform in India will not solve caste prejudice.
Reena Jaisiah has been questioned about her caste throughout her life
"There are Dalit politicians in India, but nothing has changed. The answer is to educate Dalits and empower them."
Mr Gogineni says that Dalits also discriminate amongst themselves; that there is in effect, a hierarchy even amongst the untouchables.
The National Secular Society however, does think that legislation can be used to tackle the problem in the UK.
The society's Keith Porteous-Wood wants the government to include a clause in the Equality Bill which is currently going through parliament, which would be enacted if subsequent research indicated that discrimination was apparent.
But the Hindu Forum of Britain says caste does not exist in the UK.
They maintain that the only remnant of the system is a tendency for like-minded people to seek each other out for social or marriage purposes.
Reena Jaisiah, however, is in no doubt that her Dalit origins still cast a shadow over her life.
"I own a shop in Coventry and there is one customer - who is from the higher Brahmin caste - who keeps asking me what caste I am.
"She still refuses to take the change from my hand when I serve her."