Two firefighters from the fire service's Horley-based Technical Rescue Unit (TRU) have flown out to Bosnia to help in the wake of large-scale flooding and landslides.
Mick Lewin and Charlotte Eastwell  are part of the UK team of 33 deployed as the UK International Search and Rescue Team (UK ISAR).
The team, which also  includes firefighters from Hampshire, Cheshire, Greater Manchester, Lincolnshire, Merseyside, West Midlands and Mid and West Wales, went into action after a call for help from Bosnia and Herzegovina.
The appeal for assistance followed dreadful weather which has hit local communities hard in Bosnia and Serbia, burying homes and leaving thousands of people stranded.
Mick and Charlotte, known as Charlie, and both part of West Sussex Fire and Rescue Service's TRU, are working in the area of Tuzla, and are primarily responsible for organising logistics for the UK team.
Using a range of water-response equipment including four rigid inflatable boats, the team have already carried out 42 rescues, including a number of vulnerable and elderly people who were trapped and unable to swim to safety.
They have also been delivering vital food and water supplies to those choosing to stay in their homes.
Chief Fire Officer for West Sussex, Sean Ruth, said: "We're proud that we have a specialist team of firefighters in West Sussex who are trained and equipped to respond to this kind of disaster locally, nationally and internationally.
“We don't yet know how long the mission will last, but the team are self-sufficient for ten days and are working round the clock to support this life-saving search and rescue operation."
West Sussex Fire and Rescue Service's TRU is one of 21 specialist search and rescue teams strategically situated around the UK.
The teams are primarily funded by central Government through its New Dimensions programme.
The programme, which was launched following 9/11, provides the UK with a more resilient response to major incidents such as widespread flooding, structural collapses, terrorist attack and transport emergencies.
Thirteen of these teams are trained to be deployed overseas as part of the UK response when a foreign government appeals for help after a natural disaster.
The TRU consists of 12 specially trained West Sussex firefighters who have been part of the International Search and Rescue (ISAR) team, which in recent years has responded to  international rescue missions in Haiti, New Zealand and Japan.