Abstract: A method and system for delivering advice to patients suffering from respiratory conditions based on changes in environment, such as weather or air quality changes. This system includes a patient specific model which uses input environmental data to predict changes in the patient's condition. The model is developed from an analysis of patient's responses to a variety of environmental triggers, and can be refined with time. The model can include only those specific triggers appropriate to a patient, can include the delay between the change in environment and change in condition of the patient, and can be run with data which is geographically localized to the patient's location. Conveniently the models can be run on personal devices held by the patients, such as mobile telephones, which are in communication with a server and/or a provider of environmental data.