The best prospects are those who are wealthy and who have a genuine affinity with your cause. And what better place to find them than your own database? Which is why the bulk of this section is taken up with the various ways of searching your database.
But wait! Before you start ploughing through your database, do not overlook those who give to similar causes to your own.
Many significant individual and trust donors are listed on annual reports, so create a list of those organisations with a similar cause and check out their annual reports. These are generally available to download from the organisation's website or you could write to them asking for a copy. If you do not know their website address, or you cannot find it after a web search, it may be listed on the Charity Commission's Register of Charities.
If you are not sure which organisations have similar causes to your own, you can find out by doing an advanced search on GuideStar UK.