From humble beginnings in 2003, Movember has grown from a joke to a challenge, and from a challenge it became a global philanthropic movement for men's health.
The modern moustache isn't just for hipsters and rugby league players; it's a force for good that raised $124 million last year, across 14 countries, for prostate cancer and male mental health.
Founders Travis Garone and Luke Slattery are two men on a mission - to cultivate facial hair and men's wellbeing in the month of November.
"We were having beers and we stumbled across this idea, it was a joke and going to be fun," Mr Garone told news.com.au.
"The appeal of Movember to most guys is to have a good excuse to grow facial hair - be a bit disruptive, maybe upset the boss.
"Once you start wearing it, it's a catalyst for conversation."
(Need some inspiration? Check out this gallery of splendid facial hair)
There are a few conversations the Movember boys want you to have.
Beyond the campaign's obvious fun side (we'll encourage you to join our #movember campaign on Instagram in a moment), there's a powerful call-to-action behind every hairy upper lip that benefits partners such as the Prostate Cancer Foundation of Australia and national depression initiative beyondblue.
In 10 years Movember has raised $302 million towards these two causes, drawing its initial inspiration from the power and success of the breast cancer awareness movement.
This year, the Movember and Sons campaign encourages men to share knowledge from generation to generation.
"There are two sides to every moustache," Mr Garone said. "There's the fun, crazy side - growing mo's and having beers with your buddies, then there's the serious men's health side."
"We always wanted to make it fun while being serious so we thought: 'let's laugh in the face of danger'."
"This is a time to ask your mates how they're going - stop the jokes for a minute and inquire about your buddies, ask them about their health and tell people what you're going through mentally and physically.
"By talking about things, you'd be surprised how you can help. Remind yourself you're wearing it for a particular reason and have that conversation.