This paper describes the algorithm used by a multi-strategy dialogue manager (DM) for a speech-based dialogue system and presents the results of an evaluation of the new DM. From its different dialogue strategies the DM is capable of determining the most appropriate strategy based on a set of criteria and the corresponding algorithm. The DM can adopt a number of styles ranging from highly naturalistic mixed-initiative dialogues to rigid system-led dialogues, taking into account factors such as user experience and recognition conditions.