In order to gain and retain public confidence, you must be absolutely clear about who funds you. This can be difficult if donors want anonymity. You must respect requests for anonymity but clarify this in your accounts. In this case, you can expect to have to answer ongoing questions about the identity of the donor(s). To protect your good name further, it is vital that you have proper cash handling procedures, especially if you raise money from the general public.
Never, ever forget to thank donors!