Everyone needs a good friend to turn to in times of need. Even Tinseltown's A-listers enjoy a good giggle and a gossip - and who better to share that with than another celeb with whom they can compare plastic surgeons, swap stories about George Clooney's kissing style or head to Kabbalah classes together? Here are some of the best buddies in Hollywood...

Courteney Cox, 41, and Jennifer Aniston, 36
How they met: They were co-stars on Friends for more than ten years - and it was their real-life friendship which prompted them to sign on for an additional year to the show.

What they do together: Hang out at the Cox-Arquettes. Jen is godmother to Courteney and David's daughter Coco, and after her split from Brad Pitt she bought a house next door to the couple who offered her a lot of support during her high-profile break-up.

Why their friendship works: 'We have a kind of pact,' says Courteney. 'If anything ever bothers us, we don't hold it in for one second. From the first day we met, Jen would just drag me out and start telling me stories about her relationships. She's an all-round friend and she's incredibly loyal. We went through our relationships and break-ups together, through my wedding to David Arquette and my father dying. I love, love, love her.' In return, Jen praises Courteney for being loyal and 'a girl's girl.' 'She's not stand-offish, she's not threatened by women - she's comfortable,' she says. 'And that makes you feel comfortable. I see Courteney every week - I like to think we will be friends forever.'

Nicole Kidman, 38, and Naomi Watts, 36
How they met: They became friends as teenagers when they tried out for the same commercial, and Nicole was instrumental in helping Naomi make it in LA. 'If it wasn't for Nicole providing so much inspiration, I might have packed up and gone home,' says Naomi.

What they do together: As two major A-list Hollywood players, work features a lot in their time together these days - be it at red carpet events or fundraising functions. But Naomi denies her famous pal pulled any strings to get her breakthrough roles in Mulholland Drive and The Ring. 'You can't just call someone and say, "You need to hire this person,"' she says. 'Ultimately they have to get it on their own merit.'

Why their friendship works: Because they give each other support. Naomi moved in with Nicole and was her rock after Nic split from Tom Cruise in 2000, and Nicole, who is now married to singer Keith Urban, returned the favour when Naomi and Heath Ledger called it quits in 2004. 'She handled everything so gracefully. I'm in awe of her,' says Naomi. 'We've always been there for each other,' adds Nic.

Drew Barrymore and Cameron Diaz
How they met: As the producer of Charlie's Angels, Drew picked Cameron to play Natalie and the two got close during filming. And Drew is gagging to reunite on-screen with her pal for a third Charlie's Angels film. 'I would give anything to do a third,' she says. 'I think about it all the time.'

What they do together: These bubbly blondes love a good time and enjoy the outdoors life - be it at the beach or just out and about in LA where they both live.

Why their friendship works: 'Cameron's my best friend in the whole world,' says Drew, who has also revealed she would love to be her blonde buddy's bridesmaid if she ties the knot with Justin Timberlake. 'I think the best thing is to love your girlfriends unconditionally and to find girlfriends who are girl's girls, who want the same things as you,' adds Cam. 'I've made some very good new female friendships along the way and they've become among my most important relationships because they love me unconditionally. We look out for one another.'

Kirsten Dunst and Maggie Gyllenhaal
How they met: On the set of Mona Lisa Smile, starring Julia Roberts, in which the two hit it off on-set.

What they do together: Maggie introduced her brother Jake to his on-off girlfriend Kirsten, and the pair often spend time with Maggie and her partner Peter Sarsgaard. They enjoy a low-key life away from the spotlight, and often share meals and walks together in New York.

Why their friendship works: Both are level-headed and fun-loving. With a baby on the way for Maggie and Peter, Kirsten reportedly can't wait to be a godmother for her pal's little one - and Uncle Jake has such a sexy ring to it!

Gwyneth Paltrow and Madonna
How they met: The duo united over their love of Pilates and yoga, as well as art, healthy living and music.

What they do together: They are often spotted in the front row at fashion shows, and also go to fitness classes together. Gwyneth was maid of honour at Madge's wedding in Scotland.

Why their friendship works: Madonna was Gwyn's rock after the death of her father, Bruce Paltrow, and has also helped her when she became a mum for the first time to Apple. 'She has been someone to lean on. She always has the answer,' says Gwynnie, who is very protective of her high-powered pal. 'I love Madonna. She is really driven - she was actually doing Pilates with broken bones.'

Nicole Richie and Lindsay Lohan
How they met: The super-slim twosome share a love of parties and fashion.

What they do together: Go clubbing! They are regularly seen together at nightspots in LA, New York and Miami.

Why their friendship works: The girls have both faced criticism for their tiny frames and hard-partying ways. They share the same celebrity stylist, Rachel Zoe, and often share style tips. Both are also musical, and Lindsay may have been giving her skinny pal advice before Nic releases her album.

Ben Affleck and Matt Damon
Their lifelong friendship began when they were kids in Boston, then they penned Good Will Hunting that won them an Oscar for the screenplay. Sharing their dreams of becoming big film stars when they were young has kept Ben and Matt inseparable.

George Clooney and Brad Pitt
Ocean's Eleven cemented the friendship between this dreamy pair. They enjoyed plenty of high jinks on set, including lots of practical jokes - with Brad telling crew members to address George only as 'Mr Ocean'.

Leonardo DiCaprio and Tobey Maguire
They met on the audition circuit as kids, and have been friends ever since, partying and spending summers together. They are both successful actors these days and can often be spotted ringside at basketball games.

Heath Ledger and Jake Gyllenhaal
After their intense experiences on the set of Brokeback Mountain, Heath and Jake have become firm friends. They share more than just matching chiselled cheekbones - Jake is godfather to Heath's baby with Michelle Williams, nine-month-old Matilda.

Tom Cruise and Jamie Foxx
They starred together in Collateral and are now great friends - Jamie even gate-crashed a live interview with Tom in the UK recently to present him with a basket of goodies for new baby Suri. Tom says he wants Jamie, and fellow buddy Kanye West, to be 'uncles' to his daughter.