When disaster strikes, all over the world highly trained emergency relief workers drop their job or their sandwich and fly off to wherever the chaos is.

Within hours, this seasoned network of medics, engineers and technicians sets to work often surrounded by dangers, trauma and complicated politics. However well-oiled the international machinery for deploying, coordinating and delivering aid, it is always a giant challenge just to move about and communicate when a country has been shaken to its core, flooded or ripped to shreds by a hurricane. But some nations are getting it right and new technology is promising faster and more relevant responses.

Over the following pages, our correspondents look at the pioneers search and rescue, and the kit they need.

Within three days of the earthquake in Haiti, over 60 search and rescue (SAR) teams from all over the world had set up camp around a coordinating tent in Port au Prince. I was working nearby and was impressed by the efficiency with which roughly 2,000 rescue professionals, in their orange or red jump suits and with multiple acronyms, pitched tents each with their national flag, and proceeded to pull out generators, floodlights, satellite internet systems, portable shower kits and heavy lifting and cutting equipment. Not to mention the food and water they remembered for their 160 search dogs.

Some had more kit than others (the UK and Icelandic teams were the most impressively loaded with hardware) and some had bigger, faster teams than others (such as the US squads from New York and Virginia, while the Peru mission only had six members, but they still did their bit). Each country had its ­particular way of working – Nicaragua brought its own military escort. Despite the chaos, the overpowering smell of death and traumatised survivors all around them, most teams, almost all men, set to work with military efficiency (some were elite units of their countries’ armed forces, others were from fire brigades and others were specialised civilian volunteers).

Every morning they turned up at the UN-run coordination tent from where teams would be dispatched. The tent was a frenzy of activity and the sense of urgency to get to the people who were trapped meant there was little time for chatter. Logistics managers coordinated with cartographers who scrambled to produce up-to-date maps pinpointing key buildings and landmarks that had collapsed. SAR teams were assigned a building within a particular sector of Port au Prince, and given a map or GPS coordinates and transport and UN peacekeepers to escort them to each site.

Around town, as they worked their way through the rubble, they left their mark. Using an internationally recognised system, each team would spray symbols on buildings to let other teams know they had been checked. Gradually, more and more walls and rubble were daubed with the time, date and number of people found alive or dead.

SAR teams would often act not on hi-tech data but on tip-offs from locals about trapped people. Their structural engineers determined whether it was safe or not to enter a building. Search dogs often made the job of tracing people quicker. They barked when a person was found alive and started to dig when a person was found dead.

By evening, huddles of weary rescue workers would gather in each others’ campsites discussing their days, abuzz with excitement particularly if children had been pulled alive from the rubble. By 21.00 most teams were tucked into their sleeping bags in preparation for another intense day. Within a fortnight their job was done and their tents folded up. And from then on it was up to the next wave of relief workers to look after the survivors and start helping them to rebuild their lives.