This paper extends previous work on synthesizing state machines from requirements scenarios. It presents an algorithm to generate highly structured state machines from requirements written in an intuitive yet formally specified language. It is the first algorithm capable of generating richly structured state machines and provides a new solution to a major drawback with synthesis algorithms ' that the scenarios do not contain enough semantic information for rich synthesis. The paper was published in one of the top software engineering conferences (acceptance rate 14%) and was followed up with an ICSE 2007 demonstration paper describing a tool implementing the algorithm. RAE_import_type : Conference contribution RAE_uoa_type : Computer Science and Informatics