There has been a lot of talk in the local media about elderly drivers lately, and a push to require more frequent testing and stringent standards. Whether you are an older driver concerned about your eyesight or coordination, or a caregiver becoming more nervous about a loved one's driving ability - remember that all drivers, of all ages, need to be safe on the road and to keep others safe.
The Massachusetts Registry of Motor Vehicles website has an entire section devoted to senior drivers, including things for caregivers to watch out for, quizzes and local driving safety courses, warning signs of unsafe driving and how to report an unsafe driver.
Losing the ability to drive can be very traumatic for an older person, as it can lead to isolation and depression. Remember the feeling of freedom you had when you first got your license? Keep that in mind when you are talking to someone about not driving anymore. Think of ways they can keep their independence while staying safe - maybe it means using the town senior shuttle, or joining you on your weekly shopping trips, or even taking the money saved on insurance and gas and hiring a companion to act as a driver. Having a plan in place before taking away the keys can make the transition easier.
See also: Massachusetts Driving Law Blog