It is almost impossible to open a newspaper without reading something about the London housing market. House prices are rising at such a rate that the vast majority of Londoners can't afford to buy, are being forced out of the boroughs they grew up in, or in the worst cases, are being made homeless. If nothing is done, people will continue to be driven out of the city and London will cease to be a hub for creativity and entrepreneurship.

I hope we get a real diversity in perspectives from the good, the bad and the ugly. I love living in London so I hope there are submissions that celebrate the City while also showing that there are many challenges we need to face together.

We need to revisit that planning decision because in many cases across our capital [London], greenbelt land doesn't deserve the name. Car parks, quarries and wastelands are being protected and we are saying there isn't enough land to build the houses we need.

Let me speak frankly: separate but equal is a fraud. It is the language that tried to push Rosa Parks to the back of the bus. It is the motif that determined that black and white people could not possibly drink from the same water fountain, eat at the same table or use the same toilets.

Too often, the perspectives on housing come from journalists, politicians and property experts, with a focus on the extreme ends of the market. Through the FOURWALLS Film Project, we want to get an accurate picture of the London housing situation through the eyes of the people that live there, and promote discussion around it.

It is almost impossible to open a newspaper without reading something about the London housing market. House prices are rising at such a rate that the vast majority of Londoners can't afford to buy, are being forced out of the boroughs they grew up in, or in the worst cases, are being made homeless. If nothing is done, people will continue to be driven out of the city and London will cease to be a hub for creativity and entrepreneurship.

We need find the space to build more affordable homes in the city. That involves a number of different policy responses. For example, I've spoken about the need to rethink the greenbelt - the protected land around the edge of London that was originally intended to be protected and retained as an area of natural beauty but in many cases is neither natural nor beautiful.