Diabetic eye disease comprises a group of eye conditions that affect people with diabetes. These conditions include diabetic retinopathy, diabetic macular edema (DME), cataract, and glaucoma. All forms of diabetic eye disease have the potential to cause severe vision loss and blindness. Diabetic retinopathy involves changes to retinal blood vessels that can cause them to bleed or leak fluid, distorting vision. Diabetic retinopathy is the most common cause of vision loss among people with diabetes and a leading cause of blindness among working-age adults. DME is a consequence of diabetic retinopathy that causes swelling in the area of the retina called the macula. Controlling diabetes—by taking medications as prescribed, staying physically active, and maintaining a healthy diet—can prevent or delay vision loss. Because diabetic retinopathy often goes unnoticed until vision loss occurs, people with diabetes should get a dilated eye exam at least once a year. Early detection, timely treatment, and appropriate follow-up care of diabetic eye disease can protect against vision loss. Diabetic retinopathy can be treated with several therapies, used alone or in combination.