Actress Dame Elizabeth Taylor has made a rare public appearance to open an Aids research centre at the University of California at Los Angeles.
Dame Elizabeth has retired from acting
The 73-year-old, who was in a wheelchair, also announced the Elizabeth Taylor Endowment Fund to support the centre.
"There's still so much more to do," said Dame Elizabeth.
"I can't sit back and be complacent, and none of us should be. I get around now in a wheelchair, but I get around."
Dame Elizabeth has suffered severe back problems in recent years, as well as other health problems.
She retired from acting and has since dedicated her life to her Aids charity work.
She helped establish the American Foundation for Aids Research in 1985 and set up the Elizabeth Taylor Aids Foundation in 1991.
The two organisations have raised a combined $243m (£139m) for research and to improve the lives of those affected by HIV and Aids.
"Acting is, to me now, artificial," said Dame Elizabeth.
"Seeing people suffer is real. It couldn't be more real.
"Some people don't like to look at it in the face because it's painful. But if nobody does, then nothing gets done."
Dame Elizabeth was joined at the dedication ceremony by musician Tom Petty and actress and writer Carrie Fisher.
Dr Edwin Bayrd, director of the UCLA Aids Institute, called Dame Elizabeth the "the Joan of Arc of Aids activism".