Interlanguage and Learnability, the published version of Yip's doctoral dissertation, examines some salient aspects of Chinese speakers' English Interlanguage (CIL) with insights from the Principles and Parameters Theory and research in language typology. On the basis of the Subset Principle and the notion of preemption, the book addresses learnability questions of how the second language learner progresses or fails to progress in the acquisition of English. The author has presented the book carefully and logically with the goal of readability in mind, which makes the book accessible to an audience interested in second language research but with little theoretical background or knowledge of Chinese linguistics. Another commendable quality of the book is the author's ability to interrelate CIL features that can easily be wrongly treated as separate and independent and analyze them in a holistic way.