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.
Walter Lam is President and CEO of the Alliance For African Assistance. He was born in Uganda but went to the US as a refugee and now lives in San Diego, California.
I left Uganda in 1986. I came to the United States as a visitor, changed my status to a refugee, and then finally got my Green Card here.
When I came to the United States, one thing that I recognised was that there were no programmes that were trying to assist Africans who were coming to San Diego as refugees.
I truly believe this was a plan of God - he brought me here, and now I can see why
That was what prompted me to start the organisation.
The Alliance For African Assistance helps refugees that are fleeing persecution, and helps them settle here in San Diego, by providing all the basic assistance that they need to start their new life.
After seeing the help we were giving to African refugees, refugees from other parts of the world came to our office asking for the same kind of assistance.
That was why we decided to help refugees from all over the world - Afghanistan, Bosnia, Sudan, Somalia, Sierra Leone - all the hotspots.
I feel like I'm a community servant, serving the people here.
People may call me a community leader, but as far as I am concerned I am a servant of the people.
At the moment we are also working with internally-displaced people in Uganda.
We want to help refugees on the ground in Uganda so that they will not even think about coming to the US to settle.
Very very few refugees are given permission to settle in the US and it would be wrong for us to give the impression to refugees around the world that all of them can come to live here.
So we want to help these people to stay in their home countries and make their life as bearable as possible, so that they will not even think about coming out here.
It's very important that whatever I learn here I can use to help people in Uganda, and that is what I am doing at the moment.
I miss home, but I feel that I can do a lot right here at the moment.
I truly believe this was a plan of God. He brought me here, and now I can see why.
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