More and more young people now go to university. But what's on offer for those who don't? Public and political attention is far more focused on the university route. Paul Johnson discovers why other kinds of further education and training have been neglected, leaving many young people facing much more difficult choices. Yet the needs of the economy and the choices of many shrewd young people suggest non-university education may be heading for revival.

Producer: Chris Bowlby

How do the authorities, business and the public perceive and respond to the risk of violent terrorism?

With unprecedented access to the work of an active MI5 officer, home affairs correspondent Dominic Casciani discovers the depth of the challenge facing the security services. Just how do MI5 operatives go about filtering hundreds of weekly tip-offs into a few key leads? In a world of online radicalisation and increasing hate crime, how can they prioritise those that pose a real and immediate threat to the public, and avoid wasting resources on red herrings and keyboard warriors?

He also hears from:

- Paul Martin, who led security preparations for the London 2012 Olympics

Would we be safer if we knew more about the threats that face us, or should we be kept in the dark?

Presented by Dominic Casciani

David Edmonds examines how algorithms are used in our criminal justice system, from predicting future crime to helping decide who does and doesn’t go to prison.

While police forces hope computer software will help them to assess risk and reduce crime, civil rights groups fear that it could entrench bias and discrimination.

Analysis asks if these new computer tools will transform policing - and whether we need new laws to regulate them.

Contributors

Producer: Diane Richardson

Climate change has shot up the current political agenda in part due to the Extinction Rebellion protests. An urgent question now facing UK policymakers is whether they should accelerate the adoption of cutting-edge green energy technology to curb the country's carbon emissions. But are there dangers of being an early adopter of new technology? What happens if it doesn't work or if it's outpaced by newer technologies which are cheaper and more efficient? The BBC's Business Editor, Simon Jack, investigates.

Women are paid less than men and do more unpaid work. The gender pay gap doubles after women become mothers. Female-dominated professions tend to be lower-paid than male-dominated ones. What's going on and can we fix it?

Reporter: Mary Ann Sieghart

Maintenance is an unfashionable word. But as Chris Bowlby discovers, keeping our infrastructure in good condition is one of the most crucial and creative challenges we face. Key assets such as concrete bridges built in the early post-war decades are crumbling, and may be what one expert calls 'ticking time bombs'. And all kinds of systems, even in the digital world, still need maintaining well. But all the focus for politicians and many engineers is on brand new infrastructure, not sustaining the vital assets we already have. So how can we learn to value maintenance in a radical new way?

Producer: Chris Bowlby

For centuries we have met our other halves through family, friends, work, or religious institutions. But they have all now been outstripped: meeting online is now the most common way to meet. Not long ago, finding love online was considered unconventional. Now the ping of dating apps is the soundtrack to many people's lives.

Producer: Ant Adeane

Will the growing competition between China and the United States inevitably lead to military conflict? One leading American academic created huge attention when in 2017 he posed the idea of what he called a "Thucydides Trap". Drawing on the work of the ancient Greek historian, he warned that when a rising power (Sparta) threatens an existing power (Athens) they are destined to clash, unless both countries change their policies. He warned that the same pattern could play out with the US and China. Since then, President Trump has engaged in combative rhetoric over trade, while China has fast been modernising and upgrading its military. BBC Diplomatic Correspondent Jonathan Marcus considers whether Washington and Beijing can escape the trap - or whether the growing economic, strategic and technological rivalry between the two nations will inevitably end in conflict.

Will human actions result in the demise of huge numbers of other species - in a mass die-off, comparable to the end of the era of the dinosaurs? Neal Razzell assesses the evidence that species are dying off at a rapid rate, and looks at some of the surprising things we might do to slow or reverse this process.

What is the chance of the human race surviving the 21st century? There are many dangers – climate change for example, or nuclear war, or a pandemic, or planet Earth being hit by a giant asteroid.

Around the world a number of research centres have sprung up to investigate and mitigate what’s called existential risk. How precarious is our civilisation and can we all play a part in preventing global catastrophe?

Contributors

Anders Sandberg, Future of Humanity Institute.

Film clip: Armageddon, Touchstone Pictures (1998), Directed by Michael Bay.

Presented (cheerily) by David Edmonds.