In 2002, then-mayor of London Ken Livingstone launched the 100 Public Spaces Programme, a campaign to better realize the potential of the city's public realm. With guidance from Jan Gehl, the initiative emphasized reclaiming space for pedestrians and enhancing street life.

Soon after Boris Johnson defeated Livingstone in last year's election, the new mayor shook up the city's public space plans, drawing fire from his predecessor. Some projects, like the pedestrianization of Parliament Square, got the ax, while others moved ahead. Last month, Johnson announced a re-vamped public space campaign, which he's calling "Great Spaces."

In her Streetfilms debut, Alice Shay speaks to Paul Harper, a head urban designer at Design for London who managed the 100 Public Spaces Programme. Here he discusses the origins of the program and guides us through projects currently underway in East London's Aldgate neighborhood, including a one-way to two-way conversion and the creation of a new public park.