German-Swedish writer Jakob von Uexküll thought there weren't enough Nobel Prize categories to truly address the challenges faced by humanity.
So in 1980, he founded the Right Livelihood Award, widely known as the "alternative Nobel Prize."
Over the last four decades, 174 people from 70 different countries have been awarded the prize. This year, the recipients hail from Western Sahara, China, Sweden and Brazil.
What all the nominees have in common is their commitment to fight for justice, self-determination and a better future.
"With the 40th Right Livelihood Awards we honor four people whose leadership inspires millions of people to defend their rights and fight for a livable future on planet Earth," said Ole von Uexküll, Jakob von Uexküll's nephew and the current executive director of the Right Livelihood Foundation.
'Gandhi of Western Sahara'
By the time she was a teenager, Aminatou Haidar was already an activist. She has continued to campaign peacefully for the independence of her home country, Western Sahara, ever since.
Morocco annexed the territory shortly after the former Spanish colony gained its independence in 1975, and its authorities have discriminated against the region's Sahrawi indigenous people ever since.
Haidar has become the face of a movement that is committed to Sahrawi self-determination, and fights for their fundamental human rights to be respected. She is also co-founder and president of the Collective of Sahrawi Human Rights Defenders (CODESA) humanitarian organization.
Read more: Two years, two months and nine days in hell
Haidar has organized demonstrations, documented torture and gone on a hunger strike to draw attention to the plight of her people. These actions are often not tolerated by Moroccan authorities: Haidar has been imprisoned without being charged or tried many times. She even spent four years in a secret prison isolated from the outside world.
Yet in the face of harassment, attacks and death threats — including against her children — she continues to fight tirelessly for a solution to the long-standing conflict in Western Sahara. Her enduring stamina and nonviolent protests earned her the moniker "Gandhi of Western Sahara."
The jury said she was chosen to for her "steadfast nonviolent action, despite imprisonment and torture, in pursuit of justice and self-determination for the people of Western Sahara."
A Chinese lawyer devoted to women's rights
It wasn't until 2014, when official figures were released, that it became known just how endemic domestic violence is in China: one in four married Chinese women is beaten by their husbands. It was a topic that had long been hushed up.
Two years later, the Chinese government passed a law against domestic violence, an achievement owing to the tireless efforts of women's rights activists like Guo Jianmei.
Guo is one of China's most prominent women's rights lawyers. Over the past 25 years, she and her team have provided free legal advice to 120,000 women.
More than 4,000 complaints have been lodged demanding women's rights and promoting gender equality. She is the first lawyer in the country to work full-time in non-profit legal assistance.
Guo supports campaigns on issues such as unequal pay, sexual harassment and widespread employment contracts that prohibit pregnancy across the country.
In rural areas, Guo helps women who are denied land rights where patriarchal systems leave women dependent on their husbands.
She founded an association of more than 600 lawyers that handles cases in the country's most remote regions.
Guo received this year's award "for her pioneering and persistent work in securing women's rights in China."
United for Indigenous protection
The Amazon is burning, and the world is worried about the effects the burning rainforest will have on the climate. But local inhabitants are feeling the immediate impact.
The award organizers wanted to draw attention to the plight of the indigenous people of Brazil by jointly recognizing Davi Kopenawa Yanomami, one of Brazil's most respected advocates for the indigenous peoples, and the Hutukara Yanomami Association, which he founded in 2015.
Kopenawa belongs to the Yanomami tribe, one of Brazil's most populous indigenous tribes with some 35,000 members.
Including the adjacent Venezuelan Yanomami area, it forms the largest tribal rainforest territory in the world, an area larger than Greece.
The well-known Hutukara Yanomami Association is committed to protecting the rights, culture and lands of the indigenous people of the Amazon region. Increasing destruction and deforestation for agricultural purposes poses a threat to the environment, but also to the livelihood of the indigenous people.
In the 1980s and 1990s, gold miners destroyed villages, shot people and spread diseases. Now such attacks are on the increase again.
In 1992, Kopenawa was instrumental in ensuring that a 96,000 square kilometer (37,000 square mile) area in Brazil became Yanomami protected area.
He also plays a crucial role in bringing different indigenous groups together to protect themselves from exploitation. It was for this purpose that he founded the Hutukara Yanomami Association, which represents different Yanomami communities.
Kopenawa and the Yanomami Hutukara Association have been jointly awarded "for their courageous determination to protect the forests and biodiversity of the Amazon, and the lands and culture of its indigenous peoples."
Instigator of a worldwide movement
Swedish climate activist Greta Thunberg is without a doubt the most well-known of the 2019 laureates.
In August 2018, the then 15-year-old started a solitary school strike in front of the parliament building in Stockholm a few weeks before elections.
She has since become the face of a generation who view climate change as an enormous threat to their future. Her campaign has pushed for worldwide political action to limit global warming to 1.5 degrees Celsius (2.7 Fahrenheit).
Around the world, millions of young people have joined her in skipping school and taking to the streets for the "Fridays for Future" demonstrations, which culminated in a huge global climate strike last Friday.
Thunberg speaks at major conferences and meets with world leaders. Her message is clear: Humanity must acknowledge climate change, the urgency of the crisis and act accordingly.
Thunberg has been awarded "for inspiring and amplifying political demands for urgent climate action reflecting scientific facts."
The jury added that she is "the powerful voice of a young generation that will have to bear the consequences of today's political failure to stop climate change," and that her efforts have inspired millions of people to take action.