This is the Bible on the living systems we see around us in today's world. Years ago, a reviewer described Miller's theory as "fundamental yet capable of elaboration in great detail." No one has explained it better.
Here Miller lays out 19 processes which every living system needs to perform in order to compete and survive; eight processes for information, nine processes for matter and energy, and two processes for both. Miller also sees that there are billions and billions of different kinds of living systems in the world from microscopic cells to international organizations. So, he has categorized them into seven levels from the simplest and tiniest to the most complex and largest. And, he frequently makes interesting comparisons across these different levels.
Miller weaves volumes of information about the life sciences into his theory, particularly the biology of evolution. The concept of "emergence" appears to be its bedrock. New characteristics emerge as living systems become more complex, miraculously it would seem. In that sense, the book appears to be a detailed proof of Aristotle's famous conclusion that "the whole is more than the sum of its parts."
Many readers of this book have described it as a reference book, which it is. But, that description sells the book too short. Miller's prose is graceful and readable. I would say this book is enjoyable and well worth reading even if you have only enough time to read one chapter.
Two interesting companions to Living Systems would be Kevin Kelly's Out of Control: The New Biology of Machines, Social Systems, and Economic Order and also Ruppert Sheldrake's Morphic Resonance: The Habits of Nature. It might be said that Living Systems is a sequel to Alfred North Whitehead's famous book Process and Reality.