Effective altruists do things like the following: *Living modestly and donating a large part of their income--often much more than the traditional tenth, or tithe--to the most effective charities; *Researching and discussing with others which charities are the most effective or drawing on research done by other independent evaluators; *Choosing the career in which they can earn most, not in order to be able to live affluently but so that they can do more good; *Talking to others, in person or online, about giving, so that the idea of effective altruism will spread; *Giving part of their body--blood, bone marrow, or even a kidney--to a stranger. In the following chapters, we will meet people who have done these things.