This is a graduate level text — you will need mathematical maturity as well as a decent background in both logic and abstract algebra (the deeper your background the more you can gain). When I first purchased this book I had a difficult time appreciating the subtleties of the model theoretic approach to logic. Having had some time to ponder them, I have developed a deep appreciation of its power. Model theory is to predicate logic what analysis is to engineering calculus, it is enlightening, it is logic for grown-ups.

Marker's presentation is terse, for the most part he gives his definitions and theorems with very little comment. This is unfortunate because the essence of these definitions and theorems can usually be explained intuitively with just a sentence or two of plain English, much to the benefit of the learner. Also, there are a fair amount of typos, some of them damaging. For these two reasons, this book is not friendly to the beginner, and I myself did not like it at all when I first purchased it.

With that said, I have since grown very fond of this text. Marker knows his subject well and this is reflected in the logical development. The theorems, their applications, and the many examples he gives are actually quite interesting, once you are with the program. I suspect that someone who has already had some model theory will find this book especially enjoyable. I also think this text can be put to very profitable use in the classroom — there is a great deal of power lying dormant here that can be unlocked by a professor with a good intuitive grasp of the subject.

Briefly, Marker's text is difficult for the beginner but well worth the reward if you perservere. Remove the typos and this is a five star book in my opinion.