Symbiosis originally means a close and often long-term interaction between two or more different biological species. This book presents symbiosis and related concepts such as cooperation, conflicts, and confrontations between two or more autonomous decision makers from a systems sciences perspective. Such autonomous decision makers can be called agents and include human beings, companies, and governments. Indeed, these agents are not able to exist in isolation, so that interactions and mutualistic relationships with others is absolutely essential for sustainable global development. "System" is generally defined as "a set or arrangement of elements so related or connected as to form a unity or organic whole", while systems sciences are concerned with the nature of interactions among the elements rather than that of the elements themselves. Hence it is methodologically sound and natural to apply systems scientific approaches to investigate symbiosis phenomena. This book consists of two parts. In Part I a wide range of research tools, from mathematical modeling and social simulation to conceptual systems modeling, are adopted to describe, explain, and analyze symbiosis, cooperation, conflicts, and confrontations between agents by identifying them as adaptive complex systems. These are called agent-based modeling approaches. In Part II there is a discussion of how to support autonomous agents with conflicting values and opinions by facilitating and accommodating them to realize symbiosis. The focus is on applied systems thinking in particular. The concept of the thinking is first introduced, then is classified into four types. Finally, meta-methodology is referred to for investigating how to choose a specific type for a specific problematic situation.