Did you know that you can adopt a child easily if you have a UK passport and are resident in certain (mainly commonwealth) countries? This is how I adopted my son.
Once local adoption procedings are completed, you apply to your British Consulate for citizenship under section 3 (1) of the British Nationality Act 1981. The application form is available online. There is a charge for the application in the region of GBP 600 and it will take about three months to process. In the application, you need a statement from the social worker who dealt with the adoption to say that all relevant local laws were followed. You also need death certificates for the biological parents and the adoption certificate of course.
Once you receive the certificate of registration of citizenship, you can apply for a passport. You will not be permitted to reside permanently in the UK without permission from Social Services. But if you are an international traveller like me, that won't be a problem for you.
