I have friends who found this book boring, and I think I see what they mean. "Ice Station Zebra" does not have the non-stop action pace of modern thrillers. What it does have, to an exceptional degree, is vivid characterization, enjoyable writing, and a sustained build-up of tension that enables the reader to miss the occasional hole in the plot. Something I truly love about this book is that there is no fat on its frame: no gratuitous violence, zero sex, no hype. In some ways it strikes me as a model for the successful thriller in its purest form, with everything potentially inessential stripped away, and I re-read it every year or two just for the sheer fun of it.