Bottom Line Up Front (BLUF) is a writing format where you put your main point and action items at the front or top of a document. While a summary lists every major point in the document, the bottom line may hit only a few points or just one.
BLUF makes it easier for the reader to digest complex information, but don’t use it if the reader is skeptical. Instead put the bottom line at the end of the document as usual. This gives you, the writer, time to build your case before hitting them with the conclusion.