A decision memo is a short, dated document that names the question, the evidence, the options, the recommended path, and the risks accepted. Done well, it protects a business from the most common failure mode: drifting into a decision no one quite owns.
1. State the question, not the answer first
Begin with what is actually being decided, who is deciding, and by when. The discipline of writing the question often sharpens the answer.
2. Show the evidence, not just the conclusion
Three to five evidence points are enough. Each should be specific, sourced, and dated. A reader should be able to argue with the evidence, not just the position.
3. Name what could change the call
List the two or three things that, if they turned out differently, would change the recommendation. This is the most useful part of a memo, because it tells the team what to watch.
Example: A team writing a one-page memo before signing a lease may discover that projected weekday foot traffic is still an assumption. That finding changes the next step: test the location before accepting the term.
The MMK lens: MMK Consult writes decision-ready memos and feasibility notes for founders, SMEs, and institutions: short, structured, and built around the choice the room actually has to make.