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+# Fundraising Scheme
+
+This is a scheme of categories suggested by a collaboration of German fundraising organisations.
+
+SearchKit searches are bundled into the extension to support this, and a button is provided on the Contacts » Categories admin screen to load these categories.
+
+## Warning on currencies
+
+The SearchKit searches use contributions' Total Amount field for numeric comparisons, but do not include a filter for EUR contributions.
+
+- If all your contributions are EUR, this works fine.
+- If all your contributions are some other currency, you may want to edit the
+  amounts, e.g. the scheme defines a major donation as EUR 500+ and if you work in GBP you might decide that GBP 500+ is too big, and that 400 is a more suitable value.
+- If you have a mix of contribution currencies you will have to make some
+  complex edits to the SearchKit searches to make this work.
+
+## To-do: document the definitions, once finalised.
+
+Documentation is currently somewhere between the original spec, the description field in the SearchKit searches, and the actual results of the search criteria!