Parents who put their children up for adoption are to get help tracing them, under plans unveiled on Thursday.
New agencies will make it easier to reunite children and parents
New Adoption Support Agencies would act as an intermediary service and the request to make contact, by child and parent, would become a legal right.
The government is consulting on changes to the new Adoption and Children Bill, which comes into effect next year.
At present intermediary services are available in some parts of the country but not others.
When the new Adoption and Children Bill was first introduced in 2002, it only made provision for access to information after the Bill comes into effect, which is expected to happen next summer.
It did not apply to the 875,000 adoptions that have already been made since the Adoption of Children Act 1926.
Minister for Children Margaret Hodge said: "Originally, we thought that the huge number of adoptions that have occurred since 1926 would mean the adoption agencies would be overburdened by applications from people seeking contact with former birth relatives."
But, following criticism from the Children's Society and other organisations, the government was forced to reconsider.
Ministers aim to introduce the changes in two stages - the first applying to adoptions made between 1926 and 1975 and the second all adoptions after that time.
Ms Hodge said: "The stages recognise that those birth relatives who placed a child for adoption many years ago and are now elderly, will benefit from having access to the scheme first."
Officials believe there could be an initial surge of between 20,000 and 30,000 applications.
If the new legislation goes through, registered ASAs will try to find out the current identity of a subject, trace them and inquire if they wish to be contacted.
Ms Hodge said: "The scheme recognises some people have no wish to be traced or to have their details passed on. That wish for privacy must be respected."
Adoption Support Agencies will not be allowed to disclose any information without the consent of a subject of an inquiry.
Gill Ragsdale, who was traced by her mother in her 20s after being adopted as a baby, said the system of intermediaries was important for all parties, including adoptive parents.
"The pre-1975 families, those adoptive parents were told this could never happen. Some parents cope with it, some are very supportive. I've talked to adoptive parents who are helping their children to search.
'Fairer and friendlier'
"But some parents are very threatened, very uncomfortable with it - my parents were very uncomfortable - so it's very difficult for them to come to terms with it.
"I think they do need some support outside the family."
The government will consult on the changes until the end of July.
Last year, ministers said adoption would be made "fairer and friendlier" with greater support for would-be adopters.
It hoped to offer prospective parents stronger support and better training for their new role.
Children would also be given a bigger say, with their views made part of the adoption process.
We asked you to send in your experience of adoption. This is a selection of responses:
I was adopted in 1965 and strongly object to the new proposals. I have a wonderful relationship with my parents who brought me up and, whilst I bear no ill will towards those who gave me up for adoption, I do not believe they should have any right to trace me (even if actual contact could only be made with my consent). Personally, I would find it very unwelcome news if my original parents were attempting to trace me. I am 39 years of age, with a settled life, and have no wish or need to be traced. Further, and perhaps more importantly, I feel this would be very unfair for my (real) parents who brought me up and to whom I owe so much.
I was adopted in 1952 and was lucky enough to have been told that at an early age by my adoptive parents. I have placed my name on a register as I feel sad to think I could walk past a blood relative and never know it. I am very pleased about the intermediary concept.
Tony, Wokingham, UK
I am adopted, and I have no wish to trace my parents. The idea of them being able to trace me is unsettling; it was their choice after all. I am not bitter but I am happy now and do not wish to disrupt my present and future with a past I have already dealt with. If legislation is to come in, it must be put together with deep consultation with both those who are adopted, those who put up for adoption and those who adopted. Otherwise people will end up getting hurt and families destroyed by unwanted contact.
Tim, Berkshire, UK
I have recently traced my birth mother with the full support of my adopted family. However I think we were all taken by surprise by the resulting emotions and I feel that there needs to be a very strong support system established to help people through this very emotional process and also through the following year/s.
Jane, Blackpool, UK
I was adopted at birth in 1964 I am nervous of being contacted, as it will open old wounds. My wife and I are now trying to adopt ourselves and contact is one of the biggest issues we have to consider. At least now everyone is aware of contact but retrospective contact is tricky.
It's a personal issue which has to be treated very sensitively with each case being considered separately