7 Causes That Were Near and Dear to Princess Diana's Heart

Diana served as patron of the trust, which promotes the awareness of AIDS and helps prevent the spread of HIV. In April 1987, Diana was invited to open the UK's first AIDS ward at Middlesex hospital. While there, she was photographed shaking hands with HIV-positive patients without wearing gloves, challenging the notion that HIV/AIDS was passed on by touch. She then went on to make several hospital visits in the years following, and Gavin Hart of the National AIDS Trust later told BBC that Diana had done so much to remove the stigma of AIDS. "In our opinion she was the foremost ambassador for AIDS awareness on the planet and no one can fill her shoes in terms of the work she did."

Diana was patron of The Leprosy Mission England and Wales from 1990 until her tragic death in 1997. Diana made significant strides in tackling the stigma surrounding the disease by traveling to countries with high leprosy rates like India, Nepal, and Zimbabwe. She also dispelled the myth that it can be transferred by touch by visiting patients and touching those with the disease. "It has always been my concern to touch people with leprosy, trying to show in a simple action that they are not reviled, nor are we repulsed," she said.

Diana became president of the first hospital in the world dedicated to cancer treatment and research in 1989. She regularly visited sick patients and supported its cancer treatment and research work. Prince William became appointed president in 2007, and in a previous statement, he said, "The Royal Marsden does an extraordinary job in treating thousands of cancer patients every year. The standards of care and compassion of its staff are unsurpassed in the world. I am, therefore, delighted and honored to become President of the Royal Marsden and will do whatever I can to support its innovative and vital work.”

After her January 1997 visit to Angola, Diana became the voice of those who were wounded and physically broken by landmines. She brought to light the damages of the devices and even put her own safety at risk when she walked through a recently cleared minefield during a trip with The HALO Trust. "I’d read the statistics that Angola has the highest percentage of amputees anywhere in the world. That one person in every 333 had lost a limb, most of them through land mine explosions. But that hadn’t prepared me for reality," she said in BBC's Heart of the Matter documentary.

Following her trip, the International Anti-Personnel Mine Ban Treaty (also known as the Ottawa Convention) was signed. The treaty calls for people to do "their utmost to contribute in an efficient and coordinated manner to face the challenge of removing anti-personnel mines placed throughout the world, and to assure their destruction." Prince Harry is now patron, and he recently called for the world to become free of the weapons by 2025.

Diana was also patron of the Great Ormond Street Hospital and often visited kids afflicted with cancer or battling debilitating diseases requiring surgery. "Her support was invaluable and incalculable," a spokeswoman for the hospital told BBC. Following Diana's untimely death, the hospital set up a memorial fund in her name and held a memorial concert.

Diana became patron of the organization that helps homeless youth and teens by getting them off the streets in 1992. The charity provides temporary shelter, education help, job placement, referrals to professional services, and counseling, and Prince William took over Diana's duties in 2005. William now carries on her legacy by volunteering his time to support the organization. In 2008, William recalled the days he used to visit Centrepoint with Diana, saying, "That example of selfless service that Centrepoint represents has stayed with me, and that is why it was the first charity that I wanted to be associated with." William also said he had witnessed firsthand "the extraordinary courage of so many of Centrepoint’s young people in rising to meet such seemingly insurmountable challenges in their lives."

Diana's love for ballet was underlined by her involvement in the English National Ballet. Not only was it the only nonhumanitarian charity Diana dedicated her time to, but she frequently attended the performances with Prince William and Prince Harry. After her passing, spokesman Jim Fletcher said Diana's death left a void and she was irreplaceable.