Book excerpt: In this book an international panel of authors offer a clear, step-by-step approach to Small Incision Lenticule Extraction (SMILE), a new refractive procedure approved for the treatment of myopia and astigmatism that is a truly minimally invasive key-hole type surgery. The book opens by discussing important fundamentals of the technology, followed by a close look at the healing response. The current surgical techniques are then described in detail with the aim of providing easy-to-understand guidance for all who wish to perform SMILE surgery or to identify solutions to pitfalls that may arise during the learning curve. Further sections cover the clinical science relating to SMILE (explaining underlying principles), discuss ongoing investigations to further expand the spectrum of SMILE surgery and offer suggestions on how to market the procedure and communicate it to the prospective patient. This guide is “a must” for everyone who wishes to enter the exciting world of SMILE.