Each club is challenging supporters to join their team and be sponsored to grow a moustache for the 30 days of November so they can raise funds to top the Aviva Premiership Rugby Mo League.
To join the Worcester Warriors Movember team, click here and register.
League sponsors, Aviva, are also coming on board and will donate £2,000 to the charity on behalf of the player with the best Mo in the Aviva Premiership as voted for by fans.
A selection of the best Mos will be posted on the Premiership Rugby Facebook page and the player receiving the most 'Likes' will give his team a huge chance of topping the league's Movember table.
Aviva's Movember involvement comes as part of a long-standing dedication to raising awareness of men's health issues and coincides with the brand releasing previously unpublished details of its claims relating to male-specific cancers on the Aviva website at the beginning of November.
Aviva Ambassador Austin Healey will be joining the team. He said: "I'll be starting to shape my prize winning Mo from 1 November as part of the Leicester Tigers Team.
With the amount of testosterone in the Aviva Premiership I'm expecting some fine examples of the hairy upper lip variety by the end of the month."
To join us for Movember 2013, the month formerly known as November, when men around the world grow a moustache to raise awareness and funds for men's health, specifically prostate cancer, testicular cancer and men's mental health, click here.