1) The best list is the list of chapters, which is currently at the bottom of http://tractionbook.com/ http://tractionbook.com/. It is a bit murky as a concept

1) The best list is the list of chapters, which is currently at the bottom of http://tractionbook.com/ http://tractionbook.com/. It is a bit murky as a concept as some verticals clearly overlap, and there are thus other ways to delineate where one stops and one starts, but this is our current approach. We'd also love to know if people think we're missing ones. 2) There are some businesses that get similar amounts of meaningful customers from different channels, e.g. SEO and inbound marketing. Usually these cases are when they overlap in strategy, but sometimes they are legitimately independent. In those cases, one vertical clearly doesn't dominate in the pareto 80/20 sense, and it makes sense to focus on multiple verticals.