It’s rare that all founding partners are equally committed. How much time each will invest, what opportunity costs each will accept, and the level of ambition each has may differ. That’s especially true if one founder had the original idea and brought on the others, or if one founder devotes himself to the business full time while his co-founders hang onto their day jobs. You should all acknowledge disparities up front and address them to avoid disappointment.
You also need to hash out how you will work together during the first 90 days. Over the long haul, Bill will handle sales and marketing while Marla does tech and Kathy handles finance. But a startup’s first days are chaotic. Everyone does everything and may switch roles on a dime. In particular, people coming in from senior positions who are accustomed to structure may struggle in this volatile milieu. Establishing temporary–possibly shared–roles for the first few months is wise.
Finally, you will need to decide how to decide. Even if you have known one another for years, it is unlikely you’ll have made these kinds of high-stakes decisions together. What will be the decision-making model? Consensus? Democracy? Is there a third party to break a stalemate? It’s best to designate a single arbiter for each type of decision.