A method of executing a workflow in a computer includes representing a main workflow of at least one computer as a series of steps which are linked to define the workflow, the steps being grouped in at least two groups. The method includes representing a transition workflow as at least one transition step, the transition step not being linked to the steps of the main workflow and defining a rule for executing the transition workflow based on transitions between steps of different groups. The method includes executing in at least one computer the steps of the main workflow in an order defined by the links. The method includes evaluating the rule to determine whether the rule applies when, during the executing, a step from one of the groups is followed by a step from another of the groups and executing in at least one computer the steps of the transition workflow when the rule applies.