Praise for the first edition of Practical Object-Oriented Design in Ruby “Meticulously pragmatic and exquisitely articulate, Practical Object Oriented Design in Ruby makes otherwise elusive knowledge available to an audience which desperately needs it. The prescriptions are appropriate both as rules for novices and as guidelines for experienced professionals.” —Katrina Owen, Creator, Exercism   “I do believe this will be the most important Ruby book of 2012. Not only is the book 100% on-point, Sandi has an easy writing style with lots of great analogies that drive every point home.” —Avdi Grimm, author of Exceptional Ruby and Objects on Rails   “While Ruby is an object-oriented language, little time is spent in the documentation on what OO truly means or how it should direct the way we build programs. Here Metz brings it to the fore, covering most of the key principles of OO development and design in an engaging, easy-to-understand manner. This is a must for any respectable Ruby bookshelf.” —Peter Cooper, editor, Ruby Weekly   “So good, I couldn’t put it down! This is a must-read for anyone wanting to do object-oriented programming in any language, not to mention it has completely changed the way I approach testing.” —Charles Max Wood, Ruby Rogues Podcast co-host and CEO of Devchat.tv   “Distilling scary OO design practices with clear-cut examples and explanations makes this a book for novices and experts alike. It is well worth the study by anyone interested in OO design being done right and ‘light.’ I thoroughly enjoyed this book.” —Manuel Pais, DevOps and Continuous Delivery Consultant, Independent   “If you call yourself a Ruby programmer, you should read this book. It’s jam-packed with great nuggets of practical advice and coding techniques that you can start applying immediately in your projects.” —Ylan Segal, San Diego Ruby User Group   “This is the best OO book I’ve ever read. It’s short, sweet, but potent. It slowly moves from simple techniques to more advanced, each example improving on the last. The ideas it presents are useful not just in Ruby but in static languages like C# too. Highly recommended!” —Kevin Berridge, software engineering manager, Pointe Blank Solutions, and organizer, Burning River Developers Meetup   “This is the best programming book I’ve read in ages. Sandi talks about basic principles, but these are things we’re probably still doing wrong and she shows us why and how. The book has the perfect mix of code, diagrams, and words. I can’t recommend it enough and if you’re serious about being a better programmer, you’ll read it and agree. —Derick Hitchcock, software engineer, Cisco   “Metz’s take on the subject is rooted strongly in theory, but the explanation always stays grounded in real world concerns, which helped me to internalize it. The book is clear and concise, yet achieves a tone that is more friendly than terse.&rdqu