The BIFF Method: Answering Hostile Messages Without Feeding the Fire

When your co-parent sends a message designed to sting, everything in you wants to answer in kind. You want to correct the record, defend yourself, and point out the hypocrisy. Bill Eddy, a family lawyer, therapist, and co-founder of the High Conflict Institute, spent decades watching what happens when people give in to that urge. His answer is a four-part formula called BIFF, laid out in his book BIFF: Quick Responses to High-Conflict People, Their Personal Attacks, Hostile Email and Social Media Meltdowns.

BIFF stands for Brief, Informative, Friendly, and Firm. It is a way of writing that gives a hostile message nothing to feed on.

Eddy's central observation, drawn from years in family court and clinical practice, is that hostile exchanges run on a predictable loop. One parent blames. The other defends. The defense reads as a counterattack, which triggers a fresh round of blame. In High Conflict People in Legal Disputes, Eddy describes how people locked in this pattern focus relentlessly on the past: who did what, who started it, who is the real problem.

A BIFF response breaks the loop by refusing to play any of those roles. You still respond when a response is needed, and the response contains no ammunition. There are no admonishments, no opinions about the other parent's character, and no defenses of your own. What remains is information.

In BIFF, Eddy advises writers to imagine their reply being read aloud by a judge, a mediator, or the other parent's best friend. If any sentence would need explaining or defending, he suggests cutting it until only useful information is left.

That one test will shrink most drafts by half.

Brief. Aim for two to five sentences. Length signals emotional investment, and every extra sentence is a new surface to attack. A short reply says the matter is small and handled.

Informative. Stick to facts the other parent actually needs: dates, times, places, plans. Leave out adjectives about their behavior and justifications of yours.

Friendly. One civil touch, such as thanking them for raising the issue or wishing them a good weekend, lowers the temperature. It costs nothing, and it reads well to anyone who later sees the thread.

Firm. End the exchange. State what will happen next and stop. Eddy suggests avoiding open questions that invite debate; if a decision is genuinely needed, offer two acceptable choices and a deadline.

Suppose this lands in your parenting app on Wednesday morning:

"You were late AGAIN at the Tuesday exchange. Maya sat at the window for twenty minutes wondering where you were. You clearly can't handle basic responsibility, and maybe the court should hear about it."

Here is the reply most of us draft in our heads:

"I was fifteen minutes late ONE time because Route 9 was shut down, which you would know if you ever bothered to ask before attacking me. This from the person who completely forgot the dentist appointment last month. Threaten me with court again and you'll hear from my lawyer."

Every sentence is understandable. Every sentence also extends the fight, creates a written record that looks terrible later, and teaches the other parent that hostile messages get big reactions. Now the BIFF version:

"Thanks for letting me know the timing was a problem for Maya. An accident closed Route 9 on Tuesday and I arrived about fifteen minutes late. From now on I'll text you by 5:15 if I'm running behind so she isn't left wondering. See you Friday at 6:00."

Four sentences. The reply acknowledges the concern, supplies the facts, offers a concrete fix, and closes the topic. There is nothing in it to argue with, and that is the point.

Hostility does not always arrive as open insult; sometimes it comes as a wall of grievance about logistics. Imagine a long email accusing you of scheduling fall soccer to sabotage the other parent's weekends, revisiting three years of calendar history along the way. A BIFF reply skips the history entirely:

"Thanks for reading through the soccer schedule. Registration closed on June 30, and games run Saturdays from 9:00 to 10:30 through October. I can handle all Saturday transportation on my weekends. On your weekends you can either take him yourself or let me know by Thursday and I'll cover it. Please tell me which option works by Friday."

Notice the structure Eddy recommends for decisions: two workable options and a deadline. You are declining the argument about the past while keeping the actual decision moving forward.

The hardest part of BIFF is the gap between reading a hostile message and answering it. In BIFF for CoParent Communication, written with family law specialists Annette Burns and Kevin Chafin, Eddy offers habits built for co-parents specifically:

• Decide first whether a reply is needed at all. Insults that contain no question and no decision often deserve silence.
• Draft in a notes app rather than the reply window, and wait at least an hour when you can.
• Run the four checks in order: Is it brief? Is it informative? Is it friendly? Is it firm?
• When the stakes are high, ask a level-headed friend to read the draft and tell you what could still be cut.

Eddy is equally clear about what BIFF is for. The purpose of the reply is to end the hostile exchange while keeping practical co-parenting on track. Winning the argument is off the table, because with a high-conflict person there is no winning an argument, only prolonging it.

Over time, BIFF pays two dividends. Your written record becomes calm and factual, which matters enormously if a judge, mediator, or parenting coordinator ever reads the thread. And the volume of incoming hostility tends to fall, because messages that used to produce a satisfying explosion now produce four polite sentences and a scheduling detail. You cannot control what your co-parent writes. You can make sure that everything with your name on it is brief, informative, friendly, and firm.