The big “D” — driving, as in “the car” — is coming up fast. My son has been riding me about it since he turned 15, but I’m not sure he’s ready.

As a parent of five children of driving age, and as a professional who’s learned lots from years of riding shotgun with parents, I can offer some rules of the road.

The legal age is meaningless. What matters is the child’s social and moral age. What is his level of trustworthiness? How cooperative is he? Has he been responsible in things much smaller than driving? The best indication of how a youngster will guide a car is how he’s guided his life up to this point.

I am consistently stunned by parents who green-light a license for a kid who, for years, has been difficult, disrespectful and demanding. Their attitude seems to be, “Well, she is old enough, so I guess it’s time.” Or worse, “Life will be unlivable around here until I let her.”

Never go against your better judgment because of pressure, be it from other parents, your schedule or your child. A privilege with as many features as driving needs lots of parental pondering, prudence, patience and discernment. Way too much is at stake for anything less.

Depending on your child’s situation, you may have to completely reassess your initial driving decision. You’ve judiciously weighed all the factors, and Mario is now truly “old enough” to drive. What happens if he mishandles the privilege? (He speeds, say, or stays out too late, or returns the car stinking of an awareness-altering substance.)

Most parents ground the kid or remove the car privilege. That’s one option, but consider another: Particularly in matters of trustworthiness or integrity, a week or two without wheels may not be enough to teach the lesson. Time-limited grounding may have to yield to open-ended supervision. Only when you feel confident in Van’s maturity does the door to driving open again.

On driver-license day, after offering congratulations, inform Edsel that this is not his permanent license, despite what the state calls it. It is still a temporary permit. It may be revoked.

A few basic “automotive tips” can guide you. Implement a “good student” discount. (Only sustained good grades lead to sustained license. Grades drop, license drops.) Gas and insurance cost money. (Household cooperation is necessary to help pay operating costs.) A clean car is a drivable car. (No explanation needed.)

Respect is a two-way street. Permission to drive is a parent’s respect for the child’s unfolding independence. A child’s respect toward the parent is a must response.

Teens, and most everyone else, view driving as more age-related than character-based. Age is the least relevant factor in this decision. In the end, it all comes down not to what year the child was born, but whether or not he has grown up.

The doctor is always in

at DrRay.com.