Plug this gap by reading and doing, not by hiring. The main reason is that you're still in the early stages of establishing a product/market fit. As Steve Bla

Plug this gap by reading and doing, not by hiring. The main reason is that you're still in the early stages of establishing a product/market fit. As Steve Blank (alongside others) says, that means you need to "get outside the building." The people who are in charge of defining and envisioning the product -- the founders, or some subset of the founders -- need to be the people seeing why their product is or isn't selling. If you feel totally unclear on how sales even works, then read a book or two (starting with Steve Blank). And see if you can meet someone who either buys or sells in the industry; buy them lunch for some guidance and tips. It might be tempting to bring on board someone like that, but dividing up responsibilities early will make it vastly harder to identify real gaps in product fit. Bring on sales people only when you have a consistently replicable process for selling. In terms of marketing to end-users, you're kind of in a difficult spot in that your target market seems pretty diffuse, therefore not easy to target. If you can come up with a segment of potential users who could be unusually passionate about the product, see if you can reach those people. Go where they are; get endorsements from the people they like. Optimize your viral loops to reach or be useful to those people. Now, if you have 3 co-founders, it's not necessary for all 3 to sell and market. I'd suggest making it a primary job of 2 of them. By the way, this advice might be different in the case of other kinds of knowledge gaps. But for sales/marketing, this increasingly and by far seems like the winning strategy.