Terrorist organisations enjoy a stream of donations from supporters in countries around the world.
These can either take the form of small operators collecting from local communities or, largely in the Gulf states, big ticket donations.
"Private donations originating from the Gulf are a vital funding stream for AQ [Al Qaeda] and AQ affiliated groups," according to the report.
In the case of small operators, the report notes that there are some instances of fundraisers abusing the charity sector. In one case in 2013, two men were convicted of "fraudulently presenting themselves as charity fundraisers using high visibility vests and collections buckets bearing the name of the charity Muslim Aid."
Once raised, donations are passed to a network of facilitators who move the money to terrorist groups without detection.
They do this by making a series of small transfers at money transfer shops, small enough to not need identification documents, or by using cash couriers who take the funds across borders on their person.