Book excerpt: "Essentials in Ophthalmology" is a new review series covering all of ophthalmology categorized in eight subspecialties. It will be published quarterly, thus each subspecialty will be reviewed biannually. Given the multiplicity of medical publications already available, why is a new series needed? Consider that the half-life of medical knowledge is estimated to be around 5 years. Moreover, it can be as long as 8 years between the first description of a medical innovation in a peer-reviewed scientific journal and publication in a medical textbook. A series that narrows this time span between journal and textbook would provide a more rapid and efficient transfer of medical knowledge into clinical practice, and enhance care of our patients.