BBC World Service's The World Today programme is asking migrants who have been successful in their adopted countries how they got to the top of their field.
Sir Magdi Yacoub is one of the world's leading heart surgeons. He works at the National Heart and Lung Institute, part of Imperial College London, but was born in the north of Egypt.
I always wanted to be a surgeon, because I had a lot of admiration for my father, who is also a surgeon.
I also wanted to be a heart surgeon. That was motivated by the fact that my young aunt, a sister of my dad, died in her early 20s of a correctable heart disease.
Heart surgery was in its infancy, but I had heard about great surgeons in different countries, including Britain.
Science and medicine stand up for all mankind - with the emphasis on all
I'd heard about particular ones who I'd targeted and wanted to go and work with and learn from them.
I couldn't have done what I have done if I had stayed in Egypt, for the simple fact that heart surgery was not developed in Egypt, and the kind of studies I wanted to pursue were not available there.
I go back regularly now, to work with my colleagues there. I have a charity called the Chain Of Hope, where we target children from poor areas where heart surgery is not available, and we offer our services.
We also offer exchanges of ideas - not only in Egypt but in different countries around the world - but Egypt is obviously a very special place to me.
When I was a child, I have all these fond memories of these places - especially places like Aswan, in the south of Egypt, which is totally inspirational.
It has a special atmosphere and special history, and is also very near to other African countries. Certain tribes come from nowhere almost, and descend on the city - tall, handsome people.
You can imagine how a young boy would react to something like that. It's really beautiful, inspirational.
Leaving Egypt and the people I loved so much, and the environment I liked, was definitely worth it, because I also have great love for medicine and science.
I actually consider myself as totally privileged to be able to serve science and medicine in a global fashion, because science and medicine know no boundaries.
As many people in the past have articulated, science and medicine stand up for all mankind - with the emphasis on all.
To pursue that wherever, and try in a humble modest way to offer it back to a community where one lives, where one has lived in the past, but most importantly globally, is very important.
To be part of science and medicine and to pursue at the very highest level, in an intellectual environment which allows that, is very important.
I have been very very lucky to be part of that.
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