What are the general similarities and differences between systems
theory, complexity theory, and chaos theory?

Interesting question, ixeman-ga 

Different people may have different perspective and classification.
I consider this to be a fair summary: 
 
System theory, some aspects of operational research, cybernetics and 
Complexity studies have this in common:
 They call on methods and principles from physics, biology and
engineering and later numerous other fields including philosophy,
sociology, organizational theory, management, psychotherapy (within
family systems therapy) and economics among others and use
mathematical tecniques and computer models to describe aspects common
to organisms, organisations and anorganic systems.

Chaos and game theory (and perhaps information theory) are
mathematical disciplines, which together with classical fields
(Differential equations, computer simulation, ..) have found
applications in these areas.

One difference is historical. Complexity theory is more recent
and one catalyst of transformation of the precursors into modern
approach was understanding of chaos. Important psychological factor
were early attempts to apply these methods to global models 
(Club of Rome: Limits to Growth and later developement by MITs
System Dynamics group:
http://www.let.leidenuniv.nl/history/rtg/oilcrisis/growth-debate.html
Ensuing debate still continues, particularly with respect to so called
'peak oil' model, theory or fact) however, method used by Forester's ,
group: continuous simulation, using ODEs (Diferential Equations) would
be not considered adequate today. Those equations (and many other)
have been shown to be chaotic and many of those atteptes fell into
disrepute.

Modern theory od Complex Systems was classified as math-application
(after an extended debate between DMOZ editors)
http://dmoz.org/Science/Math/Applications/Complex_Systems/

My personal preference would be to view it as part of physics - as it 
uses abstract and mathematical models to explain specific, concrete,
systems: organisms, societies, swarms of 'agents'.

The traditional classification of sciences:
http://www.answers.com/organic&r=67
 living vs nonliving, nature of matter,..  which gave us school subjects
 of biology, physics, chemistry, .. is no longer sufficient. Today we
know that theoretical chemistry is Quantum Mechanics and that it
applies to both organics and anorganic systems. There is no
fundamental difference betwenn organic and anorganic chemistry - it is
now issue of complexity and scale. Scale classifies
physical systems, from cosmology to nanotechnology and complexity replaced the
former clasification into living and non-living. Even the use of the
word 'organic' is changing and meaning 3. is now a common usage
http://www.answers.com/organic&r=67 

So, in summary, considering all that,
 I would classify all these fields which are not part of mathematics
as  precursors and components of an emerging field: organic physics.

Hedgie

Here are few references:
System theory 1940 -- 1970
http://en.wikipedia.org/wiki/System_theory
Cybernetics 1948 - 1990
http://en.wikipedia.org/wiki/Cybernetics
Complexity  1980 - future
http://en.wikipedia.org/wiki/Complexity
System dynamics 1960 - 1980
http://www.daedalus.es/AreasDSHistoria-I.php

A bit on the verbose side, but otherwise a great summary. Thanks for
your perspective, Hedgie!

sorry, but, this answer is muddled. cybernetics is not connected w/ physics.
i am a systems theory researcher who has organized a conference on the
subject at CUNY in New York.

take a look here
http://pespmc1.vub.ac.be/CYBSYSTH.html

and here
http://www.asc-cybernetics.org/

these are 2 good resorces where you can find basic definitions of
cybernetics/systems theory, which you can then contrast with
complexity theory, and chaos theory.

a cybernetic (systems based) answer to your question would be "within
what context will you be applying this information?"

then, you would be prompted to refine your question, leading to a more
accurate answer,
best
JS





JA

Dear Jimmy
        I believe you that you 'organized a conference' but do not think
that caused you know much about trends in physics or taxonomy of science.

I sometimes prompt authoritative comments form experts, such as this one:

http://answers.google.com/answers/threadview?id=550780

 I may enter into a brief dialog if there is some real issue or 
 idea mentioned in the comment. In this case, I can only say:

You are entitled to your opinion.

Hedgie