Which? is a consumer advocacy brand in the United Kingdom, operated by the Consumers' Association, a registered charity. The organization is committed to promoting informed consumer choice by independently testing products and services, providing impartial advice, and raising awareness of consumer rights.

One of its key offerings is the *Which?* magazine, which features detailed product reviews, buying guides, and consumer advice. The magazine maintains its independence by not accepting advertising, ensuring unbiased content for its subscribers. Which? also engages in product testing and advocacy, helping consumers make informed purchasing decisions. Its activities are primarily funded through subscriptions to the magazine, allowing it to focus on delivering reliable information without commercial influence.