2021 The 4th International Conference on Information Science and Systems encourages the community of multinational researchers to share their common experiences and discussions. In the history of the ICISS series, it has been held in three different countries. ICISS 2018 was held in Jeju Island, South Korea, ICISS 2019 was held in Tokai University, Japan and ICISS 2020 was held online due to COVID-19. With the support and acknowledgment from the delegates of the past series, we wish to pioneer a way to another outstanding event.We invite high-quality submissions describing significant, original, and unpublished results related to but not limited to any of the following topics:- Advances in Image Processing and Colorization- Agent Based Computing- Artificial Intelligence and Applications- Artificial Intelligence Aspects of Reasoning, Information, and Memory- Artificial Intelligence in Machine Vision and Graphics- Artificial Intelligence in Medical Applications- Big Data Analytics for Information Security- Business Information Technology- Communications Architectures and Protocols for the- New Generation of Networks and Computing Systems- Computational Optimization- Computer Aspects of Numerical Algorithms- Computer Science and Systems- Constraint Programming and Operation Research Applications- Cryptography and Security Systems- Cyber-Physical Systems- Frontiers in Network Applications, Network Systems and Web Services- Gamification Software for Education and Enterprises- Information Systems Management- Information Technologies for Logistics- Information Technologies for Management- Information Technology- Information Technology for Management, Business and Society Multi-Agent- Innovative Network Systems and Applications- Internet of Things, Enablers, Challenges and Applications- Internet of Things, Process Modelling and Microservices- Knowledge Acquisition and Management- Language Technologies and Applications- Lean and Agile Software Development- Multimedia Applications and Processing- Multimedia, Interaction, Design and Innovation- Programming Languages- Scalable Computing- Security, Privacy, and Trust- Semantic Information Retrieval- Smart Energy Networks and Multi-Agent Systems- Software Engineering- Software Systems Development and Applications- Systems and Simulations- Technology Enhanced Medical and Healthcare Education- Ubiquitous Home Healthcare- Wireless Sensor Networks