The Defense Innovation Unit runs on Commercial Solutions Openings (CSOs), and the front door is the solution brief — a short document (usually 5–10 pages) you submit against a specific Area of Interest. Get it right and DIU invites you to pitch, typically within about 30 days. Get it wrong and you never hear back. The single biggest mistake founders make is writing it like a traditional FAR proposal. It is not. It is a commercial pitch aimed at a government buyer who is in a hurry.
Do not submit a generic capabilities deck. Open the live solicitation and mirror its language. If the problem statement asks for a counter-UAS sensor under a cost target, your first paragraph should name that sensor, that mission, and that number. Evaluators score whether your solution actually addresses the stated need — make it impossible to miss.
Screen-out killers: writing like a FAR proposal, no commercial traction, no named military problem, and burying the ask. DIU reads dozens of briefs per Area of Interest — if your first page does not connect a real product to the stated need, you are out.
See if you qualify for an Ansys eval The MVP playbook →DIU's whole thesis is speed and de-risking. Anything you can show as already-validated shortens the path. For dual-use hardware — drones, sensors, effectors — a modeling-and-simulation package (digital twin, synthetic scenarios, hardware-in-the-loop results) lets you demonstrate performance against the mission without waiting for a live range. Reference it in the brief and bring it to pitch day; evaluators reward teams who arrive with evidence instead of promises.
Short sentences. Real numbers. One idea per paragraph. Include a one-line company overview and a summary of fundraising to date or top-line revenue — the CSO guidance explicitly asks for it. Cut adjectives, cut backstory, cut anything that does not help an evaluator say “yes, invite them.” The CSO guidebook and DIU's own best-practices page are the ground truth — read them before you write a word.
Selection means a pitch to DIU technical staff and the actual military end user, where live demos carry real weight. If you advance, you write the full proposal. So treat the brief as the audition it is: earn the pitch, and let the pitch earn the contract.
Official sources: DIU — Submit a Solution · DIU CSO Guidebook 2026 (PDF) · DIU — Commercial. Figures change; confirm on the official page before relying on them.
