Alyson Hannigan is the new ambassador for Head & Shoulders.

The 'How I Met Your Mother' actress will appear in advertising campaigns for the haircare brand, targeting female customers to promote a healthy scalp and hair.

Alyson said: "I am thrilled to partner with such an iconic beauty brand. I've relied on Head & Shoulders for years."

April Anslinger, Head & Shoulders brand manager, is thrilled with the actress' appointment.

She said: "Strip away the cameras and red carpets and Alyson is just like us, a working mum juggling a hectic work schedule and busy family life who needs five minutes of me time and the right beauty products to help kick start her day. We're excited to share that same relatable lifestyle along with her trademark humour, quirky personality and of course, her beautiful hair, with our female consumers."

Alyson will also be involved in the brand's Good Girlfriend Guide, an online manual offering advice on a diverse range of subjects, including beauty and relationships.

Fans can submit their own tips via the Head & Shoulders' Facebook page and the best 50 will be included in the ebook, with five women chosen to attend a VIP launch with Alyson in Los Angeles in November.