More Than Just a Pretty Face: Big-Hearted Celebs

01 of 16

JESSICA SIMPSON

USO supporter Simpson mingles with troops while performing in Kuwait for Operation MySpace. "I get to serve my country by doing what I love to do in front of thousands of brave men in uniform," Simpson says. "It's every girl's dream!"

02 of 16

KATE WALSH

The Private Practice star's puppy love is in full Bloom – that's the pooch in the picture – during Pedigree's 4th Annual Adoption Drive in New York's Times Square. Last year $1.6 million was raised for needy strays.

03 of 16

JENNY MCCARTHY

The former Playboy model has been one of autism research's biggest advocates since her son Evan, 5, was diagnosed with the developmental disorder. Her annual Ante Up for Autism benefit raised $325,000 in 2007. Says McCarthy, who devotes her time to the nonprofit Talk About Curing Autism: "I will work my a– off raising awareness for autism and banging down doors to get answers."

04 of 16

SCARLETT JOHANSSON

Oxfam spokeswoman Scarlett Johansson gets in on the game, playing with students from a Dalit school in Northern India. "It was an incredible opportunity to see the grass-roots approach being taken by non-governmental organizations, such as Oxfam, toward reconstructing the lives of this devastated country," says Johansson. The sexy star recently put herself up for auction to benefit the charity.

05 of 16

NATALIE PORTMAN

"I didn't know anything about poverty," Portman, in Uganda to film a documentary for the Listen Campaign, told the New York Times. "I knew it existed, but I

didn't know to what extent. These initial trips to the developing world [were] probably the most important moment of my growing up."

06 of 16

LEONARDO DICAPRIO

A staunch environmentalist, DiCaprio produced and narrated The 11th Hour – and founded the accompanying online network – to focus on the urgent changes needed to save the environment. "We, as citizens, leaders, consumers and voters, have the opportunity to help integrate ecology into governmental policy and every day living standards," he says.

07 of 16

DREW BARRYMORE

"I have seen with my own eyes what a difference a simple cup of nutritious porridge can make in a child's life," says Barrymore, who recently presented the World Food Programme a $1 million check on The Oprah Winfrey Show and cohosted a silent auction of photographs taken during her trip to Africa.

08 of 16

BRAD PITT

"The words of one elderly man who is determined to return to New Orleans led to the name of our organization: He asked us, directly, simply and profoundly, to help 'make it right.' So that's what we're doing," says Pitt of his Pink Project, which will build 150 sustainable and affordable houses for the Hurricane Katrina victims of the city's Lower 9th Ward.

09 of 16

MADONNA

Since adopting her son David from Malawi, the pop singer has started Raising Malawi, a charity aimed at helping the thousands of orphans in the African nation. "Now that I have children

and what I consider to be a better perspective on life – I have felt responsible for the children of the world," says Madonna, who teamed up with Gucci to raise $3.7 million for the cause.

10 of 16

KRISTIN DAVIS

The Sex and the City star travels to Soweto, South Africa, for an Oxfam conference on AIDS, spending much of her trip learning about what community workers are doing to combat the disease. "These people are inspirational, but can't win the battle on their own," says Davis. "These communities need nurses and doctors. These wonderful people are holding up their communities and need our support."

11 of 16

SHAKIRA

The UNICEF ambassador walks with the children from Rajshahi, Bangladesh, on a goodwill tour of the cyclone-affected region last year. "We visited a variety of education programs, and I came away with a clear sense that education is a powerful tool to improve people's lives," says Shakira.

12 of 16

VICTORIA BECKHAM

The famous mother of three stripped down for fashion designer Marc Jacobs's charity T-shirt to raise money for

the NYU Skin Cancer Foundation. Says Beckham, "Since we moved to California I have realized how important it is to practice safe sun for myself, and to keep my three boys' skin well protected as well."

13 of 16

MATT DAMON

Standing among the cotton fields of Chongwe, Zambia, Damon continues his crusade for better living conditions in Africa. He has co-founded a clean water charity called H2O Africa that

gives drinkable water to needy communities. "The promises America and other rich countries have made to Africa must be more than words," says Damon.

14 of 16

HAYDEN PANETTIERRE

The Heroes cheerleader – and active member of Save the Whales – paddles out to stop Japanese whale hunters during the annual Dolphin amp Whale Cove Peaceful Demonstration in the town of Taiji. "It was that awful feeling of knowing we really couldn't do anything about it. And we were pretty much as helpless as they were," says Panettiere.

15 of 16

HILARY SWANK

"I have lost multiple family members to cancer and witnessed their struggle first hand. I've never heard of anything quite like Pantene Beautiful Lengths, and I'm proud to be asked to promote the goals of such a unique and heartfelt program," says Swank, who shed 9 inches of her lovely locks on The Oprah Winfrey Show to donate to the charity.

16 of 16

ANGELINA JOLIE

Jolie comforts a Burmese mother while visiting the country's refugees in New Delhi, India, as a UNICEF ambassador. "The wonderful thing that I have learned since I have been in India is there are many, many needs for your own people and yet you have all been so gracious and been so open to so many refugees over the years," she says.