Rectal thermometers, while slightly more accurate, don't sound like any fun for either the taker or the giver. This is a wonderful ear thermometer that even remembers what the last 10 temperatures that were taken were. That's great when baby is sick and momma can't remember things. Note: I've been told that rectal thermometers also work under the arm, but Allyssa was much too squirmy for me to feel like I ever got a good reading. Ear thermometers are the way to go!