Forum conveniens determines whether a court should exercise writ jurisdiction based on convenience and part-cause connections. The principle of forum conveniens requires courts to assess whether they are the most appropriate forum by weighing convenience of parties and witnesses, existence of a more suitable forum, costs and applicable law. A mere part of the cause of action within territorial limits does not automatically compel jurisdiction; courts must perform a balanced, holistic assessment of forum conveniens before exercising writ or supervisory jurisdiction.