This book aims to provide new research methods, theories and applications from various areas of industrial economics and engineering. In detail, the included scientific papers analyse and describe communication processes in the fields of industrial economics, industrial system, industrial security and engineering and other related areas. The variety of the papers delivers added value for both scholars and practitioners. This book is the documentation of the IEIS 2021 conference.  The book covers a great deal of research achievements in industrial restructuring strategy, industrial organization, industrial policy, departmental economic research, industrial competitiveness, regional industrial structure, national industrial economic security theory and empirical research, and it emphasizes on combining theory with practice. The book aims to discuss the issues in industrial economics and industrial security theories and practices. It is the documentation of IEIS 2021 conference, which took place at Shandong University. Due to the impact of COVID-19, it took place online as a virtual conference.