On Tuesday, the candidates and their staff will meet at an undisclosed location, open up their laptops and begin answering questions from other Twitter users. Their responses will have to be limited to Twitter's constraints.
"While there are some City issues that are complex, this debate will boil the issues down to solid, short, responses," said event organizer John Freneye.
Questions that have been submitted in advance will take up the first portion of the debate, with live questions feeding into the Twitter stream will take up the second half.
Interested in fielding a question? Simply write it up on Twitter and use the hashtag #ANP13.