The race to become Mayor of London has started with a bang - with both the Conservative and Labour candidates promising to dramatically increase the number of new homes built in the capital.
Whilst London has a particularly acute housing shortage, it also presents a challenge for developers. The city is ringed by the metropolitan green belt, preventing further outward development, and is already heavily built up. As a result, there are often complex land assembly and remediation issues associated with even relatively modest development sites.
The easiest ways to increase housing numbers would be to increase housing density on new developments, either by shrinking the size of units or by increasing the number of floors in apartment blocks. Both small homes and tall buildings are, however, politically contentious.
Election promises are more often honoured in the breach than the observance. It will be interesting to see how the new Mayor of London delivers on these promises during their term in office.
The Conservative candidate for London mayor has vowed to double house-building in the capital, pledging to ensure homes are built at a rate of 50,000 a year by 2020. There were 21,350 new houses built in the year to September 2015. Launching his campaign, Zac Goldsmith said only he would be "able to secure the funds and powers needed from this government". Labour candidate Sadiq Khan has pledged a minimum of 80,000 new homes a year.