Aged 45, she was a member of the Redgrave acting dynasty. She collapsed on Monday after falling during a beginner's lesson on a slope in Quebec.
In a statement, the actress' publicist said: "Liam Neeson, his sons and the entire family were shocked and devastated by the tragic death, but were profoundly grateful for the support, love and prayers of everyone."
Acclaimed for her performances on stage and screen, Natasha Richardson won a Tony Award for her role as Sally Bowles in Sam Mendes' production of 'Cabaret' on Broadway in 1998.
Her other theatre credits included Eugene O'Neill's 'Anna Christie' and Shakespeare's 'Hamlet' and 'A Midsummer Night's Dream'.
On the screen her credits included: 'Patty Hearst', 'The Handmaid's Tale', 'The Comfort of Strangers', 'The Parent Trap', 'Maid in Manhattan' and 'Asylum'.
Natasha Richardson was an activist in the fight against AIDS and was on the board of the US-based charity amfAR, The Foundation for AIDS Research.
Paying tribute, a spokesperson for the charity said: "Natasha Richardson was a dedicated AIDS advocate and an eloquent spokesperson for amfAR.
"She generously contributed her time and resources to amfAR for over 15 years.
"Natasha's passion for the cause and tireless efforts gave hope and inspiration to the scientists and healthcare workers on the front lines of this deadly epidemic, as well as to the millions of people living with HIV/AIDS around the world."
this article from: http://www.rte.ie/ten/2009/0319/richardsonn.html