Chris Bain, director of Cafod, recounts how his staff responded.
"I was enjoying Boxing Day morning with my family, completely unaware of the news, when my press colleague rang and asked what our response was going to be. I turned on the news and within an hour we had called our emergency response people for a phone conference that afternoon with our partners in Caritas.
"As the scale of the disaster emerged it left us stunned, but the real horror began the next day. There was a sense that this was going to be a dominant part of our work in the years ahead.
"In many ways, this made a mockery of our plans to respond quickly to emergencies. We couldn't respond across the whole area quickly enough. By the end of the week, we had people in Sri Lanka and Indonesia joining the Caritas team. The people who responded first were our partners on the ground.
"Strengthening local capacity to respond will become a critical part of our work."