It is great to see the advent of Korean go books in English. Besides the Hankuk Kiwon Guide Book, the book Jungsuk in Our Time published by the Korean Go Association and written by Seo Bong-soo 9p and Jung Dong-sik 5p is the first one. The ISBN is 89-7990-123-2, the list price ca. USD 20. It has ca. 350 pages of size ca. A5. The printing quality may be called average for Korean standards, which means slightly worse than your typical Western go book, however, the binding is just barely good enough. The Korean translater excuses for minor language insufficiencies and as a reader one may well accept that; OTOH one wonders why a book is not even carefully proofread for obvious spelling and diagram typos. There are not many but a few more than there should be after proofreading. No, I do not criticize the English in the book (how could I dare?), but you should expect a slightly unusual usage that includes Korean instead of Japanese go terms (which are explained) and the phrase "the Whites" when referring to a group of white stones. Actually, I like that because it is short and clear. Besides it is much less surprising than the pragmatic verb "to tiger" in books by other authors.
Let's come to the contents. The book is a joseki dictionary about 3-4 joseki only. Apparently, another volume will appear later. Ca. 110 major variants of joseki are discussed. For each there are ca. 3 subvariants and each of those is justified by ca. half a dozen diagrams with one or two explanatory sentences each. Major diagrams show the full board, minor diagrams may show the full, a half, or a small part, mostly the latter. This organization of the dictionary means that there are fewer variations than in the Ishida (Dictionary of Basic Joseki) but that the offered choice of diagrams is also less overwhelming. So it is easier to read the book as if it were a text book, provided you would allow such a description for any dictionary. The comparatively few diagrams mean that analysis is by far not exhaustive and some secondary moves are not discussed at all. Contrarily one can concentrate on the discussed moves more easily. For an extensive coverage the Ishida, the Nihon Kiin dictionary, or whatever is still very much needed.
Although Korean joseki can be very large and some of them are included, the presence of some 19x19 diagrams is rather used to show some joseki that are incorporated within a fixed fuseki pattern. While this is a good thing, you should not expect too much from it. Most 19x19 diagrams show nothing but the joseki and maybe one or two almost irrelevant corner stones on an otherwise empty side of the board. I even say that such is a little misleading because additional stones elsewhere are rarely respected in the comments.
So what is special about Jungsuk in Our Time? Most importantly, many old-fashioned joseki found in the Ishida are omitted in favour of quite a respectable number of modern, and here especially Korean, joseki. To some modest extent, this fills the gap that the old Ishida has left for so many years. At the same time Jungsuk includes too few joseki to serve as own's one and only joseki dictionary. So the book is a welcome and useful extension to the Ishida.
Jungsuk is written for dan players. Players that have always wanted to try something modern will find some material, those that will want to defend against such should consider the book as well. They might take any other Korean joseki book, but this is the only one in English and, crucially, it is easily available. Strong kyu players might read the book if they are motivated or curious, however, other kyus should refrain from buying it, not only because it is just a dictionary but particularly because the Ishida has the broader coverage and the useful joseki marks.
The new dictionary is consistent in its selection of variants and styles of comments. The inherent repetition and relation of the move-sequences allows the dan player to learn a little quickly, although it requires some autodidactic skills that are useful for dictionaries anyway.
It cannot be said often enough - the book, as so many about joseki, is just a dictionary. It completely fails to give reasons for positional judgements. It even sometimes tries to hide this with illogical statements. This is not worthy a 9p coauthor and probably we see nothing but a standard marketing trick here. Although one cannot easily doubt the tactics in the diagrams, it remains a little sad to leave the reader alone with his positional skills.
To summarize, Jungsuk in Our Time is a nice modern addition to the Ishida for dan players who are confident enough to judge themselves.