InStyle's Shining Stars

Matt says

: "We work with communities in developing countries to help them fund, design, and build their own water-supply systems. In the end it's a really easy solution-but one that makes an incalculable amount of difference."

Learn More: Visit water.org to donate, sign up for monthly updates, and learn how to spread the word about the global water crisis.

Go Social: Follow water.org on Twitter and Facebook

Taylor says

: "Nashville is the town I love the most in the world, and when the floods hit in May, many people in my community experienced significant loss. [The city] has recovered in the most incredible way, but there are still people here who are struggling to put their lives back together. I know we'll get there, but it'll take time."

Learn More: Visit grammy.com/musicares to donate or learn how to throw a fundraiser in your area.

Christina says

: "After I became a mom, I felt passionate about the fact that no child should go hungry. Food is not a luxury. This year, I became an ambassador for the United Nations' World Food Programme, which helps feed people in need and supports their self-sustainability around the world."

Learn More: Learn what $1 a day can buy for a hungry child at fromhungertohope.com.

Go Social: Follow World Food Programme on Twitter and Facebook

Ashton says

: "We formed DNA-which stands for Demi and Ashton-with the goal of eliminating sex slavery worldwide but first and foremost right here in the U.S. Our new Real Men awareness campaign takes aim at the people who support the slave trade: Because really, real men don't buy girls."

Learn More: Visit demiandashton.org to donate, write to your local elected officials, and volunteer to become a part of the DNA Advocacy Team.

Go Social: Follow the DNA Foundation on Twitter and Facebook.

Juliana says

: "My friend Jenifer Estess, a theater producer, was diagnosed with the neurodegenerative disease ALS when she was 35. Jenifer and her sisters began Project A.L.S. in order to help further the cause of stem-cell research, and I believe it's vital to finding a cure. So far we've had great success."

Learn More: Visit projectals.org to donate, volunteer, or to learn how to host a fundraiser in your area.

Go Social: Follow Project A.L.S. on Twitter and Facebook.

Hugh says

: "I've traveled with World Vision to Cambodia and Ethiopia. We encourage self-sufficiency by teaching people about microfinance and technology. When you give people the ability to help themselves, you make them feel like a worthy investment, and so they become one."

Learn More: Visit worldvision.com to donate and sign up for updates on Hugh Jackman's trips and the organization's efforts around the world.

GO SOCIAL : Follow World Vision on Twitter
and Facebook

John says

: "I work to raise funds for Harlem Village and schools like it, and most important, I mentor kids. I tell people: Find a school in your community and decide that those kids are not just somebody else's kids. They belong to all of us."

Learn More: Visit harlemvillageacademies.org for more information on teaching and volunteer opportunities and corporate matching programs.