Finding a cofounder is more like dating than hiring. You do not get married after a first date coffee. You take your time, get to know each other, and only then commit to a marriage.
This week’s masterclass goes deep into the advice we give to our mentees in response to two of their most common questions – how do I find a cofounder? and should I give them equity?
It shows clinicians and early stage medtech founders how to map key skill gaps, meet credible people, run low-risk trials, and avoid the mistakes that sink teams.
TL;DR
- You need complementarity, not clones find people who have skills that you don’t.
- Use Hustler–Hacker–Designer to map gaps. Meet people in the right rooms.
- Run a 1–4 week trial project before you talk equity.
- Pressure test values, time, and behaviour under stress.
- When you do commit, use vesting with a cliff.
Start with roles: what do you actually need?
Most clinician-founders have first hand experience of the problem(s) they want to solve. The gaps are usually technical (build) and business (go-to-market).
A simple way to think about this is the trio that Ash Maurya describes in detail in his excellent book Running Lean:
- Hustler: customer discovery, pilots, early sales, money in.
- Hacker: builds the thing, stitches the data, ships prototypes.
- Designer: turns workflows into usable products patients and clinicians want to use.
A variation on this is the “startup square” check you have these boxes covered: product, growth, operations, and design. (We’ll do another post on these concepts soon – for now google it!)
You do not need four cofounders. You do need to know which boxes are empty. Be honest about your own time. If you have a full time clinical job with multiple clinic sessions and on-call weekends, say so. A team only works when calendars and energy match the ambition.
The dating model for cofounders
Treat this like a relationship that deepens with evidence. Take your time to get to know them. Check to see if they align with your values and whether you can work well together.
Phase 1: Coffee chats.
Swap problem stories. Ask about their experience. Compare availability and risk appetite. Note how the conversation feels. You are testing for curiosity, ethics, and care for patients, not just credentials.
Phase 2: Micro-sprint (1 week).
Pick a tiny goal or small project. Agree a rhythm of meetings. Have a washup session / retro at the end – what worked well, what didn’t. You are testing communication, speed, skills and follow-through.
Phase 3: Validation project (3–4 weeks).
Agree a clear brief, e.g. do ten problem interviews, build a clickable prototype, identify one pilot site to approach. Run this together and again check the dynamic.
Phase 4: 60–90 day push.
Now pick a bolder outcome. For digital: first working slice, a GP practice pilot target, and basic safety thinking. For hardware: a benchtop prototype, test plan, and a path to first trials. Only after this do you discuss equity and titles.
Throughout, write down how you will work: who decides what, how you communicate, and what happens if someone goes quiet. Boring is safe.
Where to meet credible cofounders
There are many programmes and platforms where you can find potential cofounders. Here are the few we have seen working well for UK founders.
- DigitalHealth.London Launchpad: support for very early digital health teams, strong NHS context, hybrid format. Good peer group and mentors.
- NHS Clinical Entrepreneur Programme: large clinician community, regular events, helpful network density even if you are pre-MVP.
- Entrepreneur First, London: structured cofounder matching and a residency to test pairings at pace. Best for full-time commitment.
- Antler, London: similar to EF, with a strong operator and engineer pool. Full-time residency.
- Zinc VC: mission-led venture builder with health themes, diverse talent beyond the usual circles.
- Events: HETT in London is dense with NHS buyers and builders. NHS Hack Day weekends are great for mixing clinicians, designers, and engineers fast. But there are loads of options, get out there and speak to people!!
- Online platforms: YC Co-Founder Matching and CoFoundersLab help widen your search beyond your postcode. Treat profiles as a starting point, not due diligence.
How to evaluate a potential cofounder
Start with values, not only skills. One rule we recommend is No A-holes! Life is too short to spend the next 5-10 years of your life with someone you don’t like.
Ask for real examples of patient safety choices, data handling, and when they chose evidence over speed. Then test time and commitment. How many hours per week? Any non-competes? Do they have employer approval for a side project if needed?
Check complementarity. Two clinicians with no builder is common. So is two builders with no one owning customers and making money. Someone must own go-to-market. Agree a simple division of tasks – who is going to do what.
See how they respond when the pressure is on, a tight deadline or an important pitch. Watch how they plan, communicate, and ask for help. Quiet competence beats loud confidence.
Finally, do your research and due dilligence, check their employment history and any previous companies, get some back-channel references. One short call with a prior collaborator tells you more than any CV.
Common red flags: equity talk on day one, vague availability, disdain for regulation and evaluation, and a record of unfinished projects.
When to talk equity (and what to say)
Do not split equity until you have worked together and delivered something. When you do, use vesting schedules (so they don’t get a big chunk of the business up front – tie it to longevity and outcomes) and get a lawyer to help you with shareholders agreements (more on both these topics in future posts).
Write a short founders’ agreement that covers IP assignment, decision-making, departures, and dispute routes. Keep titles provisional while you learn. Equity is a promise to the future. It should reflect evidence and value added, not enthusiasm.
We will publish a separate guide on founder terms. For now, the rule of thumb is clear: prove you can work together first, ensure you protect yourself and your equity. Note this doesn’t mean that you should be draconian with equity necessarily, you will need to motivate your cofounder and to strike a deal that works for both of you.
Common mistakes we see, and how to avoid them
The same traps appear again and again. Sadly we have worked with mentees who have experienced founder breakup as a result of all of these.
- Misaligned motivation. One person wants a quick exit, the other wants to bootstrap and is focussed on impact in the NHS. Write your goals down on day one and revisit them after each phase.
- Overlapping skills. Two people doing the same job leaves a gap elsewhere. Recruit to the gaps you have, find complementary skill sets.
- Equity too early. We have had to unpick all sorts of situations where everything seemed great at first, but the relationship broke down and the now estranged cofounder is sat on 20% of the business and contributing nothing.
- Side-hustle fog. Time is a precious resource, successful businesses need commitment, too many side hustles and a reluctance to give them up should raise a red flag. Put weekly hours in writing.
- No agreed ways-of-working. Agree decisions making processes, comms, tools and standards. Write them down, a team charter is a nice model for this.
- No behaviour check under pressure. Its easy to get along when the pressure isn’t on, but startups are tough, there will be downs as well as ups, you need someone that you can work with and rely on when the going get tough.
If you recognise your own situation in one of these, fix it now. Most are simple to address if you catch them early. If you leave these things to drift you are risk of pain later.
If you haven’t found your cofounder yet
Keep moving. You can make real progress on your own.
Sketch the patient journey, turn it into a simple storyboard or no-code prototype, and run ten more interviews with target users.
Write up what you learned and draft a one-page pilot brief for a practice or ward. Rent capability where needed: a day of fractional CTO time, a two-day design sprint, or a student project through a university lab.
Progress and traction attract good people. Stasis and stagnation repels them.
Cofounder scorecard
If you are meeting a lot of people and trying to decide who is the best fit you could use a simple scoring system to inform your decision. For example you could rate each person 1–5 on:
- Passion for the problem
- Ethics and values alignment
- Communication,
- Delivery under pressure
- Commitment and time available
- Complementary skills (maybe rate this out of 10 to give it extra weighting)
- Follow-through. Add one comment from a back-channel reference.
Final thought
Choosing a cofounder is one of the few decisions you cannot easily unwind. Complementary skills matter, but not at the expense of fit. You need someone you can work with, rely on, and disagree with productively.
You will spend a big part of your life with this person, so pick for shared values, working style, and the ability to show up when it is inconvenient. Take your time, trial together, and only commit when you are clearly better as a team than you are alone.
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References and resources (accessed Oct 2025)
- DigitalHealth.London Launchpad: digitalhealth.london
- NHS Clinical Entrepreneur Programme: nhscep.com
- Entrepreneur First (London): joinef.com
- Antler (London): antler.co
- Zinc VC: zinc.vc
- HETT Show: hettshow.co.uk
- NHS Hack Day: nhshackday.com
- YC Co-Founder Matching: ycombinator.com/cofounder-matching
- CoFoundersLab: cofounderslab.com