Gigi Hadid
Before attending the 2015 American Music Awards, the supermodel supports the Ryan Seacrest Foundation by meeting with deserving children at CHOC Children's Hospital in Orange County, Calif.
Brooke Burke-Charvet
The actress and her husband David Charvet attend the Petit Maison Chic fashion show honoring Operation Smile in Beverly Hills, Calif. Guests later enjoyed food from Tilted Kilt.
Jese Tyler Ferguson
The Modern Family star shows off LZZR's Tie The Knot bow tie keychain that benefits Tie The Knot's fight for LGBT rights.
Katy Perry & Jerry Seinfeld
Big night out! The A-list stars attend Citi Presents Change Begins Within, a David Lynch Foundation Benefit Concert, in New York City.
Matthew McConaughey
The actor supports The Darrell K Royal Research Fund for Alzheimer's Disease at a private event.
Britney Spears
The "Toxic" singer donates $120,000 to the Nevada Childhood Cancer Foundation after one of her Las Vegas concerts.
Melissa Joan Hart
Actress and family attend the 26th Annual Elizabeth Glaser Pediatric AIDS Foundation A Time For Heroes Family Festival.
The Pink Agenda Gala
Giuliana Rancic hits the carpet before hosting the Breast Cancer Research Foundation and FAB-U-WISH event in New York City.
Magic & Cookie Johnson
The former basketball star steps out with his wife for the Habitat for Humanity of Greater Los Angeles Builders Ball, a charity dedicated to providing affordable housing to families in need.
Jared Leto
The Oscar winner narrates a new PSA about climate change from the Sierra Club, RYOT and the Environmental Media Association.
Lisa Vanderpump
The Real Housewives of Beverly Hills star attends the StopYulinForever March to End Dog Cruelty in Yulin, China.
Sarah Michelle Gellar & Mark-Paul Gosselaar
The Hollywood stars help raise more than $1 million for Mattel Children's Hospital UCLA at the 16th annual Mattel Party on the Pier.
Kristen Bell, Jessica Alba, Jordana Brewster, Rachel Bilson & Rosemarie DeWitt
What a bunch! The celeb mamas hang out at the Alliance of Mom's Raising Baby workshop in Los Angeles over the weekend.
Melanie Lynskey, Bryce Dallas Howard & Jason Ritter
The Hollywood stars attend the 4th annual RARE Tribute To Champions Of Hope Gala in Huntington Beach, Calif.
Julie Bowen
The Modern Family star shoots her new PSA campaign for Stand Up To Cancer with CVSHealth.
Josh Altman & Joanna Krupa
The Bravo stars come together to help raise more than $130,000 at the "Get Lucky for Lupus LA" celebrity poker tournament and party at Avalon Nightclub.
Yara Shahidi
The Black-ish star partners with DoSomething.org to encourage young girls to get involved with science, technology, engineering, and math in schools.
Gayle King
In honor of International Literacy Day and Pencils of Promise, the news correspondent light the Empire State Building yellow.
Caitlyn Jenner & Chaz Bono
The reality star and actor meet with the staff at Transformng Family and Children's Hospital Los Angeles' Center for Transyouth Health and Development.
Holly Robinson Peete & Eva Longoria
The Hollywood stars come together to support the HollyRod Foundation's 17th annual DesignCare Gala. The non-profit helps with family members affected by autism and Parkinson's disease.
Bryshere Gray
The Empire star takes to the court for former Harlem Globetrotter's Allen "Duffy" Samuels' 13th Annual Celebrity Charity Basketball Game.
Shawn Mendes
The singer and Vine star joins forces with DoSomething.org on a campaign called Notes from Shawn that encourages young people to post inspiring notes in unexpected places to boost self-esteem.
JoAnna Garcia Swisher & Jenna Dewan Tatum
The gorgeous gals stun at Switch Bel Air for Shop For A Cure, a benefit for the Charlotte & Gwenyth Gray Foundation's efforts to cure Batten Disease.
Victoria Justice
The actress supports JetBlue's Soar With Reading initiative at the New York aquarium.