In this chapter, we explore the attention to fragility at play in two urban maintenance settings: graffiti removal and water networks management. Drawing on ethnographic fieldworks, we show that maintenance activities consist of situated sensorial explorations by which maintainers carefully scrutinize the state of things and become attentive to their tendency to alter and transform. Paying attention to maintainers' attention outlines ways to elaborate a specific ecological posture. Maintenance appears indeed as a situated and political process that engages materials, bodies, instruments and texts, and is accomplished through provoking and cultivating encounters within emerging ecologies wherein what acts, and what interacts, is never completely known in advance. Exploring attention to fragility thus helps to reconsider how humans interact with things beyond 'cultural' or 'symbolic' relations. Furthermore, drawing its value from repetition and constancy, the continuous attentional work that fragility requires performs a reparation that cannot be 'settled' once and for all. Far from fixing the state of things, maintenance inextricably participates in their becoming.