Giving What We Can (GWWC) is an effective altruism-associated organisation whose members pledge to give at least 10% of their income to effective charities. It was founded at Oxford University in 2009 by the philosopher Toby Ord, physician-in-training Bernadette Young, and fellow philosopher William MacAskill.

Effective altruism (EA) is a 21st-century philosophical and social movement that advocates "using evidence and reason to figure out how to benefit others as much as possible, and taking action on that basis". People who pursue the goals of effective altruism, sometimes called effective altruists, may choose careers based on the amount of good that they expect the career to achieve or donate to charities based on the goal of maximising positive impact. They may work on the prioritization of scientific projects, entrepreneurial ventures, and policy initiatives estimated to save the most lives or reduce the most suffering.