Climate interacts with infrastructure slopes and their associated vegetation to cause changes in porewater pressures and shear strength with time. Extreme events may ultimately lead to slope failure as a result of increases in porewater pressure and/or decreases in strength. In addition, certain weather conditions may also cause serviceability problems owing to excessive movements. This paper uses network-level studies of infrastructure earthwork performance, site-specific data and numerical modelling to explore the relationships between climate, geological conditions and the performance of the UK's earthworks. Key factors for understanding earthwork behaviour are identified, including plasticity and permeability. How climate change may affect UK infrastructure slopes is then considered, assessing how different failure mechanisms may become more prevalent in the future and hence the relative risk at different sites may change.