Variable Tint Lenses are convenient, fascinating, fashionable, functional and comfortable. Yet what makes this technology so unique? How are they made? How do they work? What considerations need to be addressed before recommending specific VTL lenses to our patients? Let's take a walk down memory lane and explore how and why technological advancements improved lens performance and patient satisfaction. Understand the properties of VTL lenses is key in our ophthalmic world today.