Mark Harrison's Contemporary Music Theory - Level Three is a specialized guide for jazz and pop musicians, focusing heavily on chord extensions and voicings. The book excels in breaking down complex harmony concepts into manageable steps, with exercises and answers for immediate feedback.

Pros: The structured lessons help musicians master chord extensions, making it ideal for those looking to deepen their harmonic knowledge. Users praise its clarity and practical exercises.

Cons: Some reviewers feel the book is too narrow, ignoring broader theory topics like melody construction or blues theory. The heavy focus on jazz may disappoint pop musicians expecting more variety.

Verdict: A strong resource for advanced harmony, but best suited as part of the full series—expect to invest in all three levels for comprehensive learning.