Dr. Mary Ellen Guffey: Again, this depends on the audience. Readers of some savvy magazines and newspapers would immediately recognize 24-7. But general audiences might not understand.

Kelli Viehl: Assistance is available 24 hours a day, seven days a week.

Paula Presley: 24-7 is just too, too. I might say it in informal conversation, but never in a written piece.

Karen Powers: "twenty-four hours a day, seven days a week."

Alicia Rosov: Only for casual use or slick promo material. For the company's annual report, I would write "Assistance is available 24 hours a day, 365 days a year."

Maureen McAndrews: None.

Cassie Hemphill: Externally I would never use 24-7. Within the organization, 24-7 may be acceptable in informal communications. However, except in small group or other informal settings, terms like this seem to be used primarily to show-off, and exclude "outsiders."

Rob Ault: I'd rewrite it as "Assistance is available 24 hours a day."

Yvonne Klein: ...in-house communication is a special case.

Jennifer German: Actually, it should be 24/7.....

G. Miki Hayden: Really, 24/7.

John David Lamb: A and B smack of jargon and might not be understood by some readers.

L. L. Thrasher: 24/7 is fine in speech but too slangy for writing, except in very informal messages.

John Russell: In Canada 24 most often refers to a box of beer...

Yocheved Golani: I also like 24/7. The immediacy and clarity of the term serves its purpose well.

Bob Allen: In another week or two, 24-7 will either be acceptable or will totally disappear.

Elizabeth Platt: Ick, all of them.

Cathy Schlender: Many people still aren't familiar with this term, especially older visitors.

Jacqueline S. Garnier: A is the closest to what we do. However, in our informal materials we actually present it as "24x7."

Joe McGavin: Although we have used 24/7, it's already become cliched.

Jodi Lipson: I still prefer 24 hours a day, seven days a week. (AP)

Charlotte Fox Luttrell: In our 24-7 society, I vote for 24-7, even though I personally hate it.

Paul Mulligan: I would use 24 hours a day seven days a week.

Mark H. Bloom: I use it, but I hate the phrase and all it stands for. If I was writing something more formal, I would use the third choice.

Carrie Garbas: The term "24-7" is sooo over-used.