Blyth's Haiku Seasons books and Higginson's guide to reading and writing "haiku" in English are two of the necessary books to begin to understand what haiku is all about. I have a difficult time with the idea that a tiny poem written in any of the Romance languages--esp. English-- could be called a "haiku," even though the author might include season words and even the 5/7/5 syllable count. I would much rather call them epigrams, because they simply cannot give you the effect of a Japanese haiku. Anyone who argues otherwise is simply fooling themselves, and you. Given all of that, however, Blyth and Higginson are good books to have on the shelf. Blyth, I believe, is the better writer/translator and his sense of chronology and history is stronger. In addition he gives hundreds of translated gems to admire from Basho, Issa, Buson, and others. He also doesn't try to convince you that haiku can be written in English. Higginson is the warmer writer and his generosity to the reader is apparent from the beginning, so practioners will find him perhaps more useful than Blyth in a practical sense. I disagree with Higginson's history of English language "haiku"--there are some important people he simply leaves out, but he more than makes up for the omissions in other chapters. Both writers impart an enthusiasm for the subject to their readers. If you're building a haiku library and would like a great start, Blyth's four volume set and Higginson's Haiku Handbook are the way to go.