This is the 4th edition of the book ATLAS Optical Coherence Tomography of Macular Diseases and Glaucoma. The present edition has retained most of the chapters published in 3rd edition. A chapter is added on multimodal imaging. The text is comprehensive, updated as per the present day requirements in the subject of OCT in ophthalmology. The book has 3 sections and 32 chapters. 1st section deals with introduction to OCT. 2nd and 3rd sections are dedicated to OCT in macular diseases and OCT in glaucoma respectively. OCT findings in all disease conditions are illustrated with the help of excellent coloured OCT scans. First four chapters of the book provide sound foundation of OCT by providing detail description of principle of OCT to interpretation and limitations of OCT. Chapter five to twenty five are dedicated to OCT findings and their interpretation in different macular disease conditions, e.g. diabetic macular edema, retinal vascular occlusion, age related macular degeneration, heredodystrophic disorders, photic maculopathy, retinal trauma, degenerative myopia, etc. Last seven chapters deal with OCT in glaucoma. A comprehensive index is given at last.