Avoid "success at all costs"
Motto of the Haskell Core Dev Team
As someone who is fairly associated with functional programming, have taught a number of functional languages and techniques to many teams over the past several years, I've been increasingly called on to teach specifically Haskell to curious developers. If you're looking for an excellent introductory book with practice problems and the like, I recommend Haskell from First Principles. However, not every team has the time to go through a 1000+ page book, and need to get up and running in production code quickly by leveraging existing experience with other languages.