Dr. Sims grew up in Clarion, Iowa. He attended Cornell College and graduated in 1964 from the Illinois College of Optometry. He is in general practice of optometry specializing in the fitting of contacts. Dr. Sims has been employed by several contact lens manufacturers to investigate new contact lens materials, designs, and care products prior to FDA approval. He served on the faculty of Illinois College of Optometry for two years.

Dr. Sims is a Fellow in the American Academy of Optometry, a member of the Illinois and American Optometric Associations. He is a member of the Naperville Rotary Club.

Dr. Sims and his wife Kay live in Naperville. They have three daughters. John enjoys Hiking, Biking, woodworking, and has a hardwood tree farm.

Dr. Sims maintains office hours in Naperville and Downers Grove.