Abstract: A transfer learning method for a system including a plurality of existing agents each including a trained machine learning model for modelling a respective existing machine learning scenario, and a new agent. The system includes a database comprising available models for modelling scenarios, including the trained models, existing scenario metadata indicative of existing scenarios, and transfer learning data indicative of parts of the trained models. The method comprises receiving new scenario metadata indicative of a new scenario to be modelled by the new agent, and receiving new scenario training data for training a model of the new scenario. The method also includes querying the database to: select an available model, based on the received data, to model the new scenario; and, select at least some of the transfer learning data, based on the received data, to train the selected model.