In "Four Steps to the Epiphany" Steve Blank defines an earlyvangelist as "someone who has spent money to develop a solution to a problem but is still unhappy wi

In "Four Steps to the Epiphany" Steve Blank defines an earlyvangelist as "someone who has spent money to develop a solution to a problem but is still unhappy with the result." I would use this to model you to identify which professionals to have a further conversation with: "what problem(s) have spent time or money on in the last year to reduce or eliminate where you are still unhappy with your current solution?" I would not worry about the "scaling characteristics" as much initially as finding a group of professionals who share the problem and would reference each other's decision to use your product. This does not mean that they have to know each other but that an endorsement, case study, or testimonial that describes their background and how they benefited would influence a buy decision. All innovations start in a niche, some go scale beyond that, but none scale without starting in a niche. For an elaboration on sources of innovation see http://www.skmurphy.com/blog/2008/02/15/paul-grahams-six-principles-for-making-new-things/ http://www.skmurphy.com/blog/2008/02/15/paul-grahams-six-pri... which includes checklists from Paul Graham, Peter Drucker, Gary Hamel, and Bob Bemer the inventor of ASCII.