Children no longer play in the streets as they once did and adults who want an informal game after work are frustrated by lack of spaces and by high costs for what is available in many high density areas. Pitch/Pitch is a series of stackable 5-a-side football pitches to be erected on derelict or temporarily vacant sites across London. It's designed to be a temporary installation. Fast and easy to erect, it could last for a fortnight to coincide with a World Cup tournament or for a year while a site lies dormant. It could also host other activities such as dance classes for children and adults during the day. www.ala.uk.com