Personal Positioning System (PPS) is an exploration of spatial memory in an unstable world. While the GPS gathers many different, shifting data points in order to provide us with an apparently stable representation of our position, a longitude and latitude in the earth’s grid, PPS offers alternative forms of mapping based on a more flexible unit: memory. PPS reverses the directionality of the GPS and returns to the fragmentary; it disperses rather than unifies, offshooting in different directions, overlaying the intimate on corporate territory, chasing the shifting flow of geographical information. It conceives of design as a spatial practice, one that builds fragile and temporary mnemonic structures, a virtual grid representing changing cognitive maps. PPS charts the territory of my work through three flexible units: the unit of motion, the unit of space and the unit of time. Measurement is both structural and conceptual: it partitions but it also shapes, serving as a pillar of understanding. Throughout history, units of measurement have been used to build a regimented reality, demanding adherence to schedules and modes of operating that follow militaristic and capitalistic priorities. These units speak the language of efficiency. Instead, PPS repurposes the act of measuring by using alternative units to reconfigure a ground that has already been mapped, prioritizing the circuitous and the subjective over the useful and the mechanically indifferent. The creation of parallel, more subjective units of measurement as an entrypoint to my work speaks more broadly of design as a practice of building systems that propose new ways of understanding: design as reconfiguration. Measuring here acts as an invitation to challenge existing knowledge and question our position. This thesis asks “where am I?” many times over, and the answer is always different.