Located on a constrained site in Central London, this project creates a new facility for a new type of proton beam therapy using a compact linear design developed with scientists from the CERN centre in Switzerland. Despite the challenges of working on a Grade II site, the boundaries of what could be achieved were pushed to their limits. The facility, planned across two town houses, a 15m deep basement and extending underneath the mews road, will retain the scale and charm of the original streetscape. The patient journey will beautifully encompass restored reception rooms, views across a field of lavender and a modern interior housing the latest treatment equipment.