Abstract: A computer implemented method including receiving first sensor data from a first sensor monitoring an additive manufacturing process, the first sensor data including a plurality of first sensor values; receiving second sensor data from a second sensor monitoring the additive manufacturing process, the second sensor data including a plurality of second sensor values. Each first sensor value and each second sensor value is associated with a corresponding time during the additive manufacturing process at which the sensor value was generated. Analysing the first and second sensor data to identify a first and second anomalous event that occurred in the additive manufacturing process and a corresponding first and second anomalous event time. Identifying whether the first anomalous event is a potential cause of second anomalous event based upon the anomalous event times. Generating an output based upon identification that the first anomalous event is a potential cause of second anomalous event.