"Because the field of gap junctions is so broad, the most one book can accomplish is to present well written summaries that direct the reader to the primary literature. In this regard Hertzberg and coauthors have done an admirable job. (...) Importantly, each of the chapters discusses what isn't known or is controversial about the topic at hand, information that is often missing from the journal literature. Another attractive feature is that each review is written by two authors representing different laboratories and often quite different viewpoints. For those within the gap junction community, it is interesting to observe how potentially contentious issues are negotiated. While the majority of readers will be unaware of the implications of these author pairings, they will nonetheless profit from the fact that in most cases the biases of individual researchers are deemphasized, giving a more balanced view than is sometimes the case in the secondary literature." --Cell