Bill Gates speaks to Manuela Saragosa about the future of Africa and the urgent need for the world to invest in the continent's exploding youth population.

It comes as the billionaire philanthropist and Microsoft founder launches the second annual conference in New York of his Goalkeepers initiative - a network of activists from across the world who aim to ensure that their governments fulfil the UN’s 17 Sustainable Development Goals.

But why is it that the number of children born per woman in Africa remains so stubbornly high? We ask Olufunke Baruwa, a gender and development practitioner in Africa's most populous nation, Nigeria. And are the attempts of wealthy outsiders to solve Africa's problems misguided? Teddy Ruge, an outspoken Ugandan activist and entrepreneur, tells us it's time to let a new generation of Africans take over the controls.

Producer: Laurence Knight

(Picture: Bill and Melinda Gates introduce the 2018 Goalkeepers event at the Lincoln Center on in New York; Credit: Ludovic Marin/AFP)

Most companies around the world exist with some form of hierarchy. Usually it is a vertical structure, with executive above management, which is in turn above the workforce. But there is another form, a “flat” hierarchy. Long promulgated by tech companies and start-ups in particular, flat or horizontally-structured companies operate on the principle of “Be your own boss.” Everyone chooses their agenda, their pace and in principle there is no boss to upbraid you if you make a mistake. So does it work? David Heinemeier Hansson is a founder and partner at the web services company Basecamp, a company with a “flat as possible” structure. He gives his thoughts on being the boss of people when they are their own boss. We also hear from Drew Dudley, author of This is Day One and André Spicer, professor of organisational behaviour at Cass Business School, on the potential pitfalls of flat hierarchies.

Image: Silhouetted faces in a boardroom (Credit: Getty Images)

Uganda's home-grown film industry is proving a hit on YouTube, but does it glorify violence? Ed Butler heads to Wakaliga on the outskirts of Kampala to investigate, only to get shot with fake bullets.

Programme features interviews with the American immigrant studio boss Alan Hofmanis, director and screenwriter Isaac Nabwana, special effects supremo Dauda Bisaso, and British fan Timon Singh of the Bristol Bad Film Club.

Expect the Unexpectable!

(Picture: Dauda Bisaso mans his home-made prop gatling gun; Credit: BBC)

Why are Chinese bike-share companies struggling to replicate their success abroad? Ed Butler hears from Nick Hubble, a cycling campaigner in Manchester - the UK city where Chinese firm Mobike has just scrapped its bike-share scheme. Mobike's head of growth in Europe Steve Milton describes the challenges of global expansion. Julian Scriven from rival German firm Nextbike explains why the Chinese model doesn't necessarily work in other countries, and Dana Yanocha, Senior Research Associate at the Institute for Transportation and Development Policy in Washington DC, describes the challenges faced by US cities swamped by shared bikes.

(Photo: A Mobike on a London street, Credit: Getty Images)

What happened to those who graduated straight into the worst financial and economic crisis since the Great Depression?

Kim Gittleson is one of them, and she goes in search of three others who - like her - found their career prospects straight out of university blighted by a disaster not of their making. Are they angry? Or did they actually learn some useful life lessons unique to their generation?

And how long a shadow has the grim milestone in financial history cast over their financial wellbeing and their ability to have families? Professor of sociology Kenneth Johnson of the University of New Hampshire and Lowell Ricketts of the St Louis Federal Reserve provide some of the answers.

(Picture: Students at a George Washington University graduation ceremonies in 2008. Credit: The Washington Post/Getty Images)

10 years after the failure of Lehman Brothers triggered global financial meltdown, Ed Butler hears from those who were in the middle of the maelstrom.

Lynn Gray was employed within the commercial property division in New York, while Scott Freidheim was Lehman's chief administrative officer and on the bank's executive committee. Plus the mess at the London Clearing House is retold by two employees who had to resolve some 70,000 outstanding trades that Lehman still had open as it went under.

(Picture: An employee of Lehman Brothers carries a box out of the company's headquarters building on September 15, 2008 in New York City; Credit: Chris Hondros/Getty Images)

Is the multi-billion dollar e-cigarettes industry doing more harm than good? Manuela Saragosa hears from Jack Waxman of the Students Against Nicotine campaign, who is worried about a new generation of vaping addicts in the US. Health campaigner Robin Koval explains why one brand in particular - Juul - has teenagers hooked. We hear from Dan Thompson, Juul's managing director in the UK. And is regulation about to catch up with the vaping business? Owen Bennett, global tobacco analyst at Jefferies, tells us.

Producer: Laurence Knight

(Photo: Vaper in an e-cigarette store in California, Credit: Getty Images)

Ed Butler talks to historian Adam Tooze about the legacy of the global financial crisis, which peaked with the collapse of Lehman Brothers in September 2008. Adam Tooze is a professor at Columbia University in New York and the author of a new book Crashed: How a Decade of Financial Crises Changed the World. He argues that the reverberations of 2008 are still defining much of our political and economic life, from the rise of Donald Trump in the US to youth unemployment and economic policy in Europe.

(Photo: Lehman Brothers sign being carried to an auction in London in 2010, Credit: Getty Images)

India has been developing rapidly over the past few decades. But in one way, it can still be very traditional. Women are often expected to stay at home after marriage. And that means only a quarter of Indian women are in paid work, according to the World Bank. So what's behind it? The BBC's Vivienne Nunis hears from Ajit Ranade, chief economist of Aditya Birla Group, and Radhika Kumari, founder of the Pink City Rickshaw Company, a team of female rickshaw drivers overcoming cultural barriers to break into a male-dominated field.

(Picture: Pink City Rickshaw driver Pushpa in Jaipur, India. Credit: BBC)

A compelling back story is now de rigueur when it comes to selling us things, especially in the food industry; whether it's a bar of chocolate or a cup of coffee, provenance is everything. We take a trip round London's trendy Shoreditch area with man about town and marketing expert, Peter York who explains why being 'handmade by hipsters' can justify sky high prices. Down in the depths of the British Library, Polly Russell tells us how the idea of the backstory came about. We take a leisurely stroll across town to London Bridge where Tom Sellers takes time out from service at his restaurant, Story, to wax lyrical about his culinary pièce de résistance - an edible candle. Steve Sutton, a Colombian in New York insists that sourcing beans from dangerous 'red zones' is vital to his coffee business, Devoción. And what do you do if you have a product to sell but no story to tell? Simon Manchipp from Shoreditch design agency SomeOne is here to help.

(Image: Confident Barista, Credit: Getty)

Sites offering wild theories, and unsupported claims, are increasingly the stuff of modern online discourse. But what's the business model that's fuelling their rise? Alex Jones, the prominent radio host, is pretty much America's best known conspiracy theorist. As well as warning of a deep state conspiracy against the President, he's also claimed that the government is controlling the weather, that demons are taking over America, and that school mass shootings including the 2012 attack on the Sandy Hook Elementary School that left 20 small children dead, was in fact a hoax involving child actors. Such comments, offensive to many in the US, have recently seen his shows removed from Facebook and YouTube and suspended on Twitter, saying he's violating their rules around community reporting. Apple and Spotify have also taken down his podcasts. We hear from James Bridle, the author of a book called New Dark Age: Technology and the End of the Future, on why conspiracy theories are flourishing in the internet age, and from Filipo Menczer, Professor of Informatics and Computer Science at Indiana University, and Charlie Warzel, a news reporter at BuzzFeed, who has been looking at how these sites can now raise tens of millions of dollars, largely by selling medications to followers. Plus Professor Joseph Uscinski, a political scientist and fake news expert at Miami University in Florida who says that conspiracy theories have now themselves become part of the mainstream.

(Credit: Stevanovicigor, Getty Images)

Should cities be worried about 'overtourism'? We hear from disgruntled locals in Rome, Edinburgh and Amsterdam. The BBC's Douglas Fraser reports on the dilemmas facing Scottish tourism in the face of rising numbers and Amsterdam novelist Joost de Vries describes the impact of tourists on his home city. Can anything be done? Yes, says Xavier Font, professor of sustainability marketing at the University of Surrey.

(Photo: A group of tourists in Barcelona, Credit: Getty Images)