A method of traversing a workflow is described. The workflow comprises a plurality of interconnected question and answer nodes, each question node being linked to a respective stored pre-determined question and each answer node being linked to a respective stored answer. The method comprises: determining the type of the current node of the workflow and, if the current node is a question node, accessing a data store, ascertaining whether the data store contains a previously determined answer to the question linked to the current question node and, a) if the data store does contain such a previously determined answer, retrieving the answer from the data store and using the retrieved answer to determine the next node of the workflow to be traversed; and b) if the data store does not contain such a previously determined answer, presenting the question linked to the current question node to a user, and using answer data obtained from the user to determine the next node of the workflow to be traversed.