In a context where cities are already built, it becomes essential to engage with what is already materialized and to work within the existing. Often overlooked, potential lies in the in-between. Gaps, interstices, residual space, everyday places are full of undefined voids. Lausanne is no exception. A mapping process revealed 379 gaps scattered throughout the city. Found in various types and facing strong constraints, they call for creativity. Nine sites are selected as exploration grounds for precise, small-scale interventions. Whether filling a void, keeping it open or making room for the unknown, each project takes root with a distinct intention. ONE protects a void, recognizing existing qualities and choosing not to build. TWO removes dividing lines. Going against a juxtaposition of private parcels, it invites shared use of the space to gain more from it. With minimal means, THREE defines a public function for an overlooked space. FOUR and FIVE tackle time: one provides support for future extensions and the other embraces flexible use. SIX, SEVEN and EIGHT insert themselves between buildings. Staying autonomous, extending the existing or connecting neighbors, they react to their surroundings in different ways. NINE extends upwards from the existing, embracing dualities such as open/closed and individual/collective. Through these varied responses, a common attitude emerges: making the most of what’s already there, doing more with less and reclaiming the city’s forgotten gaps.