Q: What can a woman do about the struggle for the armrest between two airline or theater seats? When women sit in a seat that shares an armrest with the neighboring seat, they typically keep their arms in their laps to avoid invading the territory of the neighboring seat. But most men immediately plant their arms on the armrests of their seats. The woman must then bring her arm even closer in, to avoid contact with the man's elbow, which slips over as the forearm rests comfortably on the armrest.

If the woman determines to place her arm on the armrest anyway, most men don't relinquish it -- so they end up sitting cozily with their arms caressing, a situation which can become downright dangerous, since many men take this to be a form of flirting on the part of (of course) the woman.

Is there a way to claim one's right to the armrest, or at least to keep it neutrally free, without being misinterpreted as seeking contact?

A: You will have to excuse Miss Manners from donning full battle regalia to fight this question out as part of the war of the sexes.

The fact is that the armrest belongs to the first person to claim it. If the victor leaves the domain, however, it may be reconquered.

Elbow intrusion may also be dealt with as a simple matter of etiquette. The person whose territory is being invaded may say "Excuse me" to get the intruder's attention and then direct his gaze to the offending joint, with, if necessary, the additional (pleasantly made) remark of, "Do you mind? These seats are so crowded."

An emergency measure is to bring one's own elbow sharply down on the intruding one, and then to excuse oneself.

Q: I am getting remarried in four weeks, and my older sister is going to be my matron of honor. When sending out invitations, I invited my ex-brother-in-law to my wedding, and he and his new wife have accepted my invitation.

My reasons for wanting to invite him, I feel, are valid and based upon mutual respect and friendship. My sister and ex-brother-in-law have been divorced for approximately five years, and until recently remained quite friendly. It was not at all unusual for him to be at family dinners (without his new wife) or various other functions.

When I informed my sister that I had invited John and he had accepted, she threw a real fit, during which she called me some pretty rotten names. She is now insisting that I un-invite him -- call and ask him not to come -- because she can't stand the sight of him now. (Evidently, they recently had a falling-out regarding monetary matters.)

She considers my invitation to him a betrayal of her. I feel what she is asking me to do is beyond reason and would show deplorable etiquette. I've told her that perhaps I made an error in inviting him, but that I cannot make another error by rescinding my invitation, which he has accepted.

A: What the modern divorce has gained in ease and acceptance, it has lost in indignation. There are simply too many divorces around to allow time and energy for the sort of widespread feud that each used to be allowed to inspire.

At the time of a divorce, each party has the right to claim a reasonable amount of partisanship from his or her own family. That is, one can make a case that one has been grievously wronged, and expect one's own relatives to offer sympathy and not continue to keep the offender in the family, entitled to be present on family occasions.

Asking them to sever all relations is unreasonable unless the offense is really blatant, and is never proper in the case of innocent parties such as children.

Your sister chose not to exercise that right. By tolerating, perhaps even inviting, his presence at post-divorce family dinners, she sanctioned your right to continue the relationship.

However, you really don't want to have an emotionally distraught, not to mention foul-mouthed, matron of honor.

Tell your sister that your invitation was based on the previous good relations between her and John, and that while you do not feel that you can decently recall an invitation, you leave her free to tell John that she would prefer not to see him there.