General Systems Theory, developed by biologist Ludwig von Bertalanffy, proposes that systems across very different domains, biological, mechanical, social, and ecological, share common organizing principles, such as hierarchy, openness to the environment, and self-regulation, that can be studied as a unified field rather than domain by domain.

Shared vision is one of Peter Senge's five disciplines of a learning organization, describing a genuinely held, collectively built picture of the future that a group wants to create together, as distinct from a vision statement handed down from leadership that people comply with but do not believe in.

A feedback loop exists when the output of a process circles back to influence its own input. Balancing loops push a system toward a goal or equilibrium, such as a thermostat regulating temperature, while reinforcing loops amplify change in one direction, such as compounding interest or a viral trend.

Soft Systems Methodology, developed by Peter Checkland, is an approach for tackling messy, real-world problem situations where different stakeholders hold different and sometimes conflicting views of what the problem even is. Rather than forcing a single model of the system, SSM builds multiple root definitions that represent each worldview.

The Viable System Model, developed by Stafford Beer, is a cybernetic framework for diagnosing whether an organization has the structures it needs to survive and adapt in a changing environment. It describes five interacting subsystems, covering operations, coordination, control, intelligence, and identity, that any viable organization must have in some form.

A wicked problem is a problem that is difficult or impossible to solve completely because it involves incomplete or contradictory knowledge, many stakeholders with conflicting values, large economic or social costs, and connections to other problems. Poverty, climate change, and public health crises are classic examples.

Chaos theory studies dynamic systems that are highly sensitive to their starting conditions, so that a tiny difference in initial values can produce dramatically different outcomes over time, popularly known as the butterfly effect. Despite the name, chaotic systems are not random; they follow deterministic rules that simply make long-range prediction practically impossible.

The iceberg model is a systems thinking framework that pictures a problem as an iceberg: the visible tip is the event, the small percentage we notice and react to, while beneath the surface sit patterns of behavior, underlying structures, and finally the mental models that give rise to everything above.

A stock and flow diagram is a modeling tool from system dynamics that separates a system into stocks, the accumulations that can be measured at any point in time such as inventory, water in a reservoir, or trust in a team, and flows, the rates that increase or decrease those stocks such as hiring, evaporation, or broken promises.

Double-loop learning describes what happens when a person or organization questions not just an action that went wrong, but the underlying assumptions, goals, and mental models that led to that action in the first place. Single-loop learning fixes the error and moves on; double-loop learning asks whether the governing variable or the goal itself needs to change.

Systems thinking is a way of understanding the world that looks at how the parts of a system relate to one another, and how a system behaves over time, rather than analyzing components in isolation. Instead of asking what single cause produced an outcome, a systems thinker asks what structure of relationships, feedback loops, and delays in the system is producing the pattern of behavior we keep seeing.