This is one of the more helpful art books I've ever read. I've been gradually learning graphic design for various side projects for some time, and I'm extremely new to custom lettering. I'm also the sort whose artistic abilities are about 1% natural talent and 99% deliberate study. I may know by intuition when something doesn't look right, but I need instruction to figure out what it is, and Castro's book provides exactly what I need.The bulk of the book is divided into two large parts. In the first, he details traditional calligraphy techniques. Even if your medium is digital rather than true hand lettering (as mine is), the section is still extremely valuable. It's much easier to make letter forms that look right when you know the mechanics behind _why_ the letters are supposed to be the way they are.The second large section shows examples of several different lettering styles, complete with multiple variations for each. For each style, there is a suggested project. He then leads you through his thought process from a preliminary sketch through several revisions, and this is where his instruction really shines. Each time he does a sketch, he critiques it mercilessly, carefully marking and explaining each detail that doesn't look quite right. Then he shows how the sketch is improved by fixing those details, and the next round of improvements begins. I've found this part incredibly useful for developing my own eye for the details. I'm already spotting things that I wouldn't have noticed in a million years without his instruction, and I just finished the book this morning.I have only one concern worth mentioning, and it isn't nearly enough to subtract a star for, especially when the book is exceptionally strong in every other respect. It's that some of his examples of variations on a style aren't very legible, and a few are downright cryptic. In the example projects that he develops in detail, he is very conscious of legibility. But for whatever reason, he still includes some other examples that I would consider too illegible to be good exemplars of a style.