For a comprehensive list of all the aid agencies involved in the relief effort to the region, and for a link to the Disasters Emergency Committee, see the links at the right of this page.
Priority
Getting fresh water to the region will be one of the priorities for the aid agencies, who will also be helping provide food and shelter, but the area is likely to need long term help.
The sheer number of countries affected, which include Sri Lanka, India, Indonesia and Thailand will make the aid effort much harder.
The first plane from the UK carrying relief supplies and equipment, which was organised by Oxfam, left East Midlands Airport on Wednesday, bound for Sri Lanka and Indonesia.
Other ways to donate
It is hoped that by the end of this week, people in the UK will be able to make donations at banks and post offices.
The Royal Mail has set up a special PO Box number which will make sure that donations to the Disasters Emergency Committee arrive speedily:
DEC Tsunami Earthquake Appeal
PO Box 999
London
EC3A 3AA
Make cheques payable to: DEC tsunami earthquake appeal
Meanwhile, Oxfam will be collecting donations in its shops, and is appealing for unwanted Christmas presents to be given to the shops which can in turn be sold to raise more money for the aid effort.
The appeal will be repeated on all BBC local radio stations at around 0900 today, this time is provisional.
And if you want to post appeals for information about a missing relative or friend, BBC News Online has set up a special page: