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Ai-jen Poo argues that we should all value caring, and carers. Ai-jen, a MacArthur Fellow, is Director of the National Domestic Workers Alliance, an advocacy organisation in the United States representing domestic workers, many of them carers. In this powerful, intimate talk, she tells the story of how two of her grandparents' very different experiences when they needed carer emphasised the importance of valuing caring. Producer: Giles Edwards

Beth Stevens talks about the brain cells most people have never heard of, and suggests what they might have to teach us. Beth is a neuroscientist and associate professor at Harvard Medical School, who in 2015 was awarded a MacArthur Fellowship - the so-called 'genius grant' - for her work on microglial cells. In this talk she describes the connections between her research and her own family history, and explains why these cells - for so long overlooked in favour of neurons - may be the key to understanding much about the brain we don't yet know. Producer: Giles Edwards

Tara Munroe reveals what she learned when she rescued some badly damaged paintings which were due to be thrown out. Tara is an arts curator and researcher. Ten years ago she found a pile of paintings marked with the words 'for disposal'. She was immediately intrigued, and as she began to research them, she became more and more drawn into their story, and how it connected with her own history. Now, a decade on, she is hoping to return them to the gallery walls, where they belong. Producer: Patrick Cowling.

Philippa Greer discusses the imprisonment of people convicted of genocide. Philippa is a human rights lawyer who has worked around the world. In this powerful talk she tells the story of a visit to West Africa to prepare for the funeral of a man who had recently died in prison. This man had been convicted of genocide, but Philippa reveals that many such prisoners will eventually be released, and what that suggests to her about the use of prison as a response to the most serious crimes against humanity. Producer: Patrick Cowling.

Nicola Reindorp, who once doubted her own abilities to be a CEO, says we should rehabilitate doubt as a strength rather than a weakness in leaders. "I'd seen my own doubts as negative, disqualifying me from leadership. I had seen others believe the same. But, I asked myself, aren't the best leaders not the ones that say they have all the answers, but those who know they don't? Not those who say they see it all, but those who ask whose perspective is missing? Rather than a deficiency to be hidden, maybe doubt should be seen as a power to be harnessed?" Nicola Reindorp is CEO of Crisis Action Presenter: Olly Mann Producer: Sheila Cook

Eva Hnizdo reflects on the impulses which drive people to emigrate - or not, drawing on her Czech Jewish family's experience of the Holocaust and her own as a political asylum seeker. "Whenever members of my family thought about emigrating but didn't actually leave, they made a mistake, sometimes paying for it with their lives. In my case, some might say I made a mistake not to stay. Was it worth the struggle?" Presenter: Olly Mann Producer: Sheila Cook Eva Hnizdo is a former GP and author of "Why Didn't They Leave?"

Robyn Travis believes that labelling children as criminals is counterproductive in the fight against violence. He says they need to be freed from the mentality that keeps them as "prisoners to the streets". "It deeply saddens me that the media, film makers and rappers alike see a beneficial gain in telling stories which further criminalise the youth of today and yesterday without losing sleep. I don't see gang members, I see prisoners to the streets." He believes in prevention rather than intervention, calling for primary school children to be taught how to avoid conflict, and for parents to stop saying, "if someone hits you, hit them back". Robyn Travis is the author of Prisoner to the Streets, Mama Can't Raise No Man and Freedom from the Streets Presenter: Olly Mann Producer: Sheila Cook

Laura Dockrill describes her frightening experience of post partum psychosis after giving birth to her son. She calls for a wider conversation about risks to parental mental health and for help to be open to everyone. "This almost invisible illness was an assassin. An apparition that nobody else could see." "Silence only inflames the symptoms, the stigma and creates an ideal culture for a mental illness to thrive. Shame, judgment and fear follow fast in the wake and it's a perfect storm, one that can unfortunately end in tragedy. But it doesn't have to. Post-Partum Psychosis is treatable." Laura Dockrill is an award winning author, illustrator and performance poet. "What Have I Done?" is her memoir on motherhood and mental health. Presenter: Olly Mann Producer: Sheila Cook

Angela Frazer-Wicks tells her extraordinary story of being a mother. Years ago, Angela's sons were taken into care and adopted, and in this powerful talk she describes her heartbreak as they gradually lost contact and she lost faith in the future. But as she explains, with support from some very unexpected places, Angela is now in a position to help other women and families going through similar experiences. Producer: Giles Edwards

Simon Morden argues that we should resist the privatisation of space. Simon is a scientist and science fiction writer, and in this talk he reflects on what science fiction has taught us. "We know about the hubris of science through Frankenstein, we know of totalitarian state-controlled media through 1984, and we also know it’s a terrible idea to break quarantine protocols through the film Alien," he says. "Science fiction doesn’t prevent us from doing those things, but we can’t say we didn’t know what the results would be." Simon is concerned that science fiction has also shown us a dark future where the coming era of space exploration - and the exploitation of extra-terrestrial objects - is dominated by private companies. And having recently written a non-fiction book about the natural history of Mars, this is a future he is keen to avoid. Producer: Giles Edwards.

Jessica Barker argues that we should rediscover overlooked sculptures of women. She didn't know it at the time, but as a child Jessica spent part of every Christmas day looking at a famous medieval monument. Later, when she became an expert in medieval art, she was angered by the phrase 'and his wife', so often associated with such monuments. Yet as she dug into the stories behind the women depicted in them, she discovered a more surprising, more subversive, and more interesting story. Producer: Giles Edwards

Steven Dowd's life changed in an instant one spring morning in 2016. In this inspiring talk, Steven describes what happened, and how a promise to his wife enabled him to regain control of the change - and his life. Producer: Giles Edwards