Choose your co-founder first, then find a market and idea together
Instead of having an idea and finding a co-founder to execute it, start by selecting a co-founder you trust deeply from years of working together. Then explore markets and ideas as a team. This ensures alignment and complementary skills from day one, rather than retrofitting a partnership around an existing vision.
When to use
When planning to start a company and you have access to talented people you have worked with for years
Don't do this
Starting with an idea and then searching for a co-founder who can execute your vision, compressing co-founder selection into weeks or months
1 Founder Who Did This
Younis's founding formula from studying startups at YC: choose co-founder first (Peter Ludwig, shared Michigan roots and Google history), then market (automotive/AV), then idea (simulation infrastructure)