CHICAGO -- So there are a few different ways to view your friend's perpetual (seriously, really, really perpetual) tardiness.
The global view: "There are large cultural differences in expectations around punctuality," says Boston-based psychologist Eric Endlich. "What is normal or 'on time' in some cultures would be considered extremely tardy in others. It can be a mistake to assume any particular motivation on the part of people who are chronically late without knowing something about their cultural background and other factors."
The optimistic view: "Planning and organizing are managed in the brain's frontal lobes, which continue to develop through adolescence and early adulthood," Mr. Endlich continues. "Thus, the ability to be punctual doesn't really peak until adulthood. There's still hope that normal maturation will help solve the problem."
The clinical view: "People with ADHD (attention deficit hyperactivity disorder) often have difficulty being on time," he says. "Because they are easily distracted, even when they intend to arrive on time they may not succeed."
Or, finally, the realist view: "It's incredibly rude," says Caroline Tiger, author of How to Behave: A Guide to Modern Manners (Quirk). "It sends a message that your time is more important than the other person's."
Regardless of your chosen perspective, at some point you're going to have to tackle the tardiness. And waiting around for her to fix the problem on her own is not an effective approach. (Besides, you've waited around long enough in this relationship.)
"Like any habit it can be changed," says Mr. Endlich. "The issue is whether the person in question wants to change. Often it is the person being inconvenienced, not the tardy one, who wants things to change."
He and Ms. Tiger have the following suggestions:
● Don't take it personally. "Some people truly don't value punctuality. It's simply not a priority for them," Mr. Endlich says. "Others may have a rebellious or passive-aggressive streak that makes them feel they shouldn't have to conform to other people's timelines." Repeat after us: It's not you, it's her. Still, your plans are being affected. So read on.
● Be a pal. You may want to (gently) point out the image your friend is crafting for herself. "Disorganized people and people who aren't in control of their lives are late a lot," says Ms. Tiger. "This is another reason not to be late, because it sends a message that you're flaky or overwhelmed."
● Stay upbeat. "Start with something positive -- 'I enjoy getting together with you' -- and focus on your goal. 'It would be great if we could find a way to synchronize our schedules better,'" Mr. Endlich suggests. "Remain open to better understanding the challenges the other person might have -- any information about the cause of the problem could help you solve it."
● Enlist technology. "Many phones and computers have the ability to provide visible and audible reminders of appointments, departure times, etc., as well as electronic calendars and maps that can help estimate how long a journey will take," says Mr. Endlich. Make sure your friend is up to speed on these modern miracles.
● Fudge. "A very effective method is to pad the time," says Ms. Tiger. "Tell her to meet you at the restaurant at 7:15 when your reservation is actually for 7:30." And bring something to read.
● Encourage rather than scold. "Think of the conversation as a brainstorming session where you can both look for possible solutions," says Mr. Endlich. "If you are overly critical or demanding, the other person may become defensive and resistant. Offer to help, 'Can you think of anything I can do to make this easier?'"
● Remember the baby rule. "New moms get a pass -- or a whole deck of passes," says Ms. Tiger. "Expect them to be late and buy them a latte -- three shots -- as a reward for making it out of the house. I don't think anyone else should (get a pass), though."