The British Red Cross said in 2008 it traced 476 people
A man who lost touch with his wife and eight children after being being forced to flee his home in central Africa, retraced them with the Red Cross' help.
Jose Mputu, who now lives in Cardiff, left the Democratic Republic of Congo in 2006 and fell into depression after being unable to contact his family.
After tracking down his wife's new address, the Red Cross network helped Mr Mputu get a message to her.
Months later he received one back and the family spoke on the telephone.
Families like Mr Mputu's, which are separated by war or disaster, can be helped by the British Red Cross international tracing and messaging service (ITMS) which works through the global network of Red Cross and Red Crescent movements to put them back in touch.
The organisation is trying to trace the relatives of more than 2,000 families who have been separated as a result of the conflicts in Afghanistan, Eritrea, Sri Lanka, Somalia, Democratic Republic of Congo, and Iraq among other countries.
Mr Mputu, who now works as a Red Cross volunteer, said he was in regular contact with his family when he first had to leave the Democratic Republic of Congo.
"I was phoning them every day. I couldn't sleep without hearing from them. I would give time to every child, sharing ideas, it was like I was with them," he said.
"One day I phoned and I couldn't get through. I thought maybe it was some trouble with the network and it would be ok. I tried again, but nothing. After a few days it became very serious. I thought, my country is in a war situation, anything could happen."
Mr Mputu was so distressed by his inability to contact his family that he needed treatment for depression.
Eventually, through friends, he managed to get an address for his family and contacted the Red Cross to help him put them back in touch.
ITMS staff asked him to draw a map of the city, and write down all the details he had of his family's whereabouts, as well as a message to them.
The Red Cross said staff and volunteers around the world hand deliver these messages to remote locations, often enquiring door to door until they find the intended recipient.
After several months, Mr Mputu discovered he had received a reply from his wife.
"It was very wonderful," he said.
"My wife wrote a message for hope. And I gripped it, I held the letter in my hand, it was like I was kissing her!
"I wrote a reply the same day and at night I put it under my pillow. I can't describe how happy I was this day."
Mr Mputu's reply included his contact details and soon afterwards he received a phone call from his wife.
"It was the first time I had heard her voice in many months. A very wonderful day again! I bought two phone cards and called her back. We spoke for two hours!" He said.
"The next day we did the same thing. I bought three phone cards and gave every child the time to talk, to express, to talk about everything.
"It's a bit like something new came into my life."
The British Red Cross ITMS said in 2008 it traced 476 people and exchanged 527 messages between families and their relatives.
More than 10% of its caseload still related to families trying to discover the fate of loved ones who they lost contact with as a result of World War II.