This book constitutes extended, revised and selected papers from the 9th International Symposium of Artificial Intelligence supported by the Japanese Society for Artificial Intelligence, JSAI-isAI 2017. It was held in November 2017 in Tokyo, Japan. The 22 papers were carefully selected from 109 submissions and are organized in sections on juris-informatics, skill science, artificial intelligence of and for business, logic and engineering of natural language semantics, argument for agreement and assurance, scientific document analysis, knowledge explication for industry.