"Rework" is a business guide written by Jason Fried and David Heinemeier Hansson, founders of the software company 37signals. The book challenges traditional business practices and emphasizes a less conventional approach to building and running a company. Fried and Hansson use their own experiences as examples to illustrate their unconventional strategies, which include embracing constraints, building half a product instead of a half-assed product, avoiding unnecessary growth, saying "no" by default, and focusing on what won't change. They also encourage a culture of openness and honesty, direct communication, and prioritizing productivity over working long hours. Overall, "Rework" presents a refreshing perspective on the world of business by rejecting traditional business models and offering alternative strategies that encourage simplicity, agility, and authenticity.