Jane Asher is to become President of the Parkinson's Disease Society (PDS), the charity has announced.
She has been involved with the Society for the last two years and recently hosted the 2006 Christmas Carol Concert.
Steve Ford, chief executive of the PDS, said: "Jane has been a firm supporter of the PDS and we are absolutely thrilled that she has taken on the role of president.
"Jane's commitment to the Society is key for us in promoting our work and helping raise funds and we are really looking forward to working with her more closely."
She will replace Richard Briers who has been president for many years.
Ms Asher said: "I am extremely honoured to have been invited to become president of the PDS – especially as I am following in the prestigious footsteps of my good friend Dickie Briers."
She went on to explain her personal attachment to the PDS when her brother-in-law was diagnosed. "I quickly became very impressed with all those involved in the charity and I'm much looking forward to working with them."
The McVities frontwoman is well-known for being the former girlfriend of Beatles member Paul McCartney and for her roles in Alfie and Look Back in Anger. She has also written various lifestyle books and novels.