The weekend’s terrorist false alarm at South Kensington will prompt a security rethink as London’s commercial real estate hunts for a way to make buildings, and their environments, safer.

Former British Property Federation Chief Executive Liz Peace said mixing security and enhanced public realm is a “conundrum” to which there is as yet no solution.

A former Ministry of Defence specialist tasked with examining London security issues, Peace said London real estate has been confronting security issues for four decades.

“In the days of the IRA we asked how you could make buildings bomb-proof. Since then the debate has moved on to how to make streets more secure. South Kensington is an interesting example because we’ve got the concept of shared space in operation on Exhibition Road. It looks beautiful but mixing cars and pedestrians in this way was always going to be difficult to manage.”

Shared space has become a popular design concept, blending pedestrians and vehicles in ways that cut vehicle speed and improve pedestrian safety. However, Peace said recent events call the concept in question.

“We have tensions here, and maybe we need to think more carefully about how the idea of shared space works?” she said.

Peace, now an advisor on property, politics and the built environment and chair of the Old Oak and Park Royal Development Corp., praised developers creating new public realm who had always sought advice from police and security experts. However, she warned further thought would be needed.

“Our need for an attractive connection between buildings and the street is at odds with the need for tougher security. This is a conundrum, we have to work out the solution and there is no quick answer,” she said.

Peace is speaking Tuesday at Bisnow's Building for the Future event at the Royal Institution, London W1. Other speakers include British Land project director Symon Bacon, AECOM Group President for Construction Services Dan McQuade and Uber Northern Cities Director Neil McGonigle.