This document introduces some key concepts of systems thinking, including that a system is more than the sum of its parts, consisting of elements, interconnections, and a function or purpose. It provides examples of systems and describes stocks and flows, feedback loops, delays, and how to analyze a system. Interventions should focus more on changing interconnections, information flows, and incongruent purposes rather than just elements. The purpose is to help the reader apply a systems thinking perspective to analyze and improve their situation.

1. Introduction to Systems Thinking:
System Structures and Behaviour
Sydney Limited WIP Society
Jason Yip
j.c.yip@computer.org
http://jchyip.blogspot.com
@jchyip

2. Select a problem as a working
example. It should be somewhat
complicated, and not too simple.

4. What is a system?

5. A system is a set of things
interconnected in such a way that
they produce their own pattern of
behaviour over time

6. A system is more than the sum of its
parts

7. http://mennodiscuss.com/viewtopic.php?f=6&t=16392#p456262

8. Systems consists of three things
1. Elements
2. Interconnections
3. Function (non-human system) or Purpose
(human system)

9. Examples of systems
● Digestive system
● Sports team
● School
● City
● Factory
● Corporation
● National Economy
● Animal
● Tree
● Forest
● Earth
● Solar system
● Galaxy
● IT system

10. https://flic.kr/p/97JeYs
“Bicycle system”

11. “Frog system”
https://flic.kr/p/mKKug

12. Systems mostly cause their own
behaviour; outside events unleash
that behaviour

13. Do politicians cause recessions and
booms? Or is it inherent to market
economies?

15. Do competitors cause companies to
lose market share? Or do their own
policies create losses that
competitors exploit?

16. “Every system is perfectly designed
to achieve the results it gets.”
Dr. Don Berwick

17. Describe your situation as a system
● What are the elements?
● What are the interconnections between the
elements?
● What is the purpose of the system?
Intended vs actual based on behaviour?

18. Stocks and Flows

19. Stocks are the elements you can see,
feel, count, or measure at any given
time

20. Examples of Stocks
● Water in a bathtub
● A population
● Books in a book store
● Wood in a tree
● Money in a bank

21. Stocks change over time via Flows
● Work flow
● Information flow
● Both inflow and outflow

22. http://lssacademy.com/2008/02/24/lets-create-a-current-state-value-stream-map/
Information Flow
Work Flow
Stocks

23. https://flic.kr/p/9az8q1
Inflow
Outflow
Information flow
Stock

24. Stocks provide a memory of flows

25. Stocks act as “shock absorbers”

26. Stocks introduce delay.
It takes time for flows to affect
stocks.

27. Delays decouple inflow and outflow

28. Examples of stocks decoupling flows
● Gasoline storage tanks
● Wood in a forest
● Water reservoir

29. “Stocks are pretty much queues”
Me

30. Let’s try describing a typical Agile
team using stocks and flows

31. How might stocks and flows change
how you describe your situation?

32. Feedback loops

33. Systems run themselves via
feedback loops

34. Balancing feedback loops
● Thermostat
● Guided missile
● Iterative, incremental software development

35. A stock with two competing
balancing loops

36. How feedback fails
● Late, lost, unclear, incomplete, hard to
interpret information
● Weak, delayed, resource-constrained,
ineffective response

37. Two competing balancing loops with
delays

38. The problem with forecast-driven
supply chains

39. A delay in a balancing feedback loop
makes a system likely to oscillate

40. Aside: This is generally solved by
using kanban

41. Reinforcing feedback loops
● Market collapse: uncertainty -> remove
money -> more uncertainty
● Compound interest
● Death march: Too much to do -> work
harder -> more bugs -> work even harder

42. A stock with one reinforcing loop
and one balancing loop

43. If A causes B, is it possible that B
also causes A?

44. How might feedback loops change
how you describe your situation?

45. Dealing with systems

46. Systems consists of three things
1. Elements
2. Interconnections
3. Function (non-human system) or Purpose
(human system)

47. Changing elements usually has the
least effect; changing
interconnections or purpose is
usually more dramatic

48. Examples
● Change all members of a sports team vs
change rules of the game or the definition of
winning
● Change people in the organisation vs
change the way of working or the definition
of organisational success

49. Focus more on interconnections and
interactions than elements
● Interaction flow / sequence over class
structure
● Work flow / value stream over org structure

50. System interactions operate through
information flow

51. Address incongruent purposes
System purposes do not necessarily match the
intention of the designers or actors within it

52. How might you intervene in your
situation to improve the system?