Rihanna, Adele, Cheryl Cole and Paloma Faith are among the stars who have taken to Twitter.com to raise awareness of World Water Day.
Russell Simmons, rocker Rob Thomas and British rapper Example have also pledged their support and encouraged the public to turn off their taps on Thursday (22Mar12) in support of the estimated 1.2 billion worldwide who do not have access to clean water.
Organisation drop4drop is calling for donations to help provide clean drinking water in third world countries - and celebrities from around the world are backing the cause.
All of the stars have asked their fans to follow drop4drop's official Twitter account, while Faith and Simmons both add: "I feel lucky every day to have clean water. A billion aren't so fortunate."
In a post on her page, Adele - whose boyfriend Simon Konecki co-founded the initiative - writes, "Today is World Water Day. A day dedicated to the billion people without clean water! Follow drop4drop and their mission #cleanwaterforall."
Pop star Mika tells followers, "I've been made aware this am (morning) by Adele that it is indeed world water day today. It's worth spreading the word when you see these stats; 884 million people do not have access to clean drinking water and 1 child dies every 5 seconds from not having clean drinking water."
Example urges his followers to keep the topic high on Thursday's news agenda, declaring, "People - can we please get #cleanwaterforall trending today? It's World Water Day!!", while Thomas adds: "let's get #cleanwaterforall trending here and then happening for real."