This thesis is centered on a single overarching research question, “when, within a crop production cycle, are farming communities most vulnerable to climate hazards?” which is addressed through exploring the integrative concept of critical moments (CMs), “periods of risk during which livelihoods are vulnerable to specific climate hazards”. The CMs concept covers different dimensions of hazard vulnerability – these being type of hazard, the time by crop stage, pathways causing losses, and potential coping strategies. A review led to the identification of three types of CMs, having a) immediate impact CMs, b) compound impact CMs, and c) shifted impact CMs. The field evidence using farm-level cross-sectional data in the Pakistani part of the Indus Basin adds to the contextual understanding of climate risks by covering farmers’ in-season coping responses, the cost, and effectiveness of coping strategies, and limitations to adjusting growing periods to shifts in seasons under climate change.