In 2013 Adam Grant, a professor at the Wharton School, published Give and Take. He sorts people at work into three types. Takers like to get more than they give. Givers pay more attention to what other people need from them. Matchers try “to preserve an equal balance of giving and getting.” Grant puts the share of matchers at about 55 to 60 percent.
One of his examples of a giver is Adam Rifkin, a serial entrepreneur whom Fortune named its best networker in 2011. Rifkin follows a rule he calls the five-minute favor: “You should be willing to do something that will take you five-minutes or less for anybody.”