Find yourself rushing around like the white rabbit from Alice in Wonderland? Leah Ingram, author of The Everything Etiquette Book, shares some timely hints on knowing when you've stretched the clock too far.

How Late is Too Late When You:

Respond to an e-mail: A few days to a week for friends, no longer than a day or two for job-related e-mails. “Not everyone checks their e-mail all the time, so one should always allow another person at least 24 hours to reply,” says Ingram. If the e-mail is regarding a job you have interviewed for, don’t take any chances — reply ASAP!

Show up at the doctor's office: Arrive any later than 20 minutes and you may be asked to reschedule.

Send a thank-you note: “A month would definitely be pushing it, but you could squeak by with a card sent two weeks after receiving a gift or attending a party,” says Ingram.

Arrive for work: If your boss watches the clock closely and you plan to show up at your desk any later than 15 minutes, call and let your office know you’re running late, suggests Ingram. Are you an hourly employee? If so, be on time!

Wait for a friend to join you at a restaurant: Half hour is a reasonable amount of time to wait for a friend who’s running late. “If you can’t get in touch with her after 30 minutes, leave a message and let her know you have to go,” adds Ingram.