Assertiveness is on a continuum. On the left side is being passive, in the middle is being assertive and on the right side is being aggressive. Passive-Assertive-Aggressive.

Being passive means not showing any sign that someone is irritating you at all. Being assertive means telling someone the way their behavior makes you feel and then letting it go. Being aggressive is any form of disapproval where you do not tell the person the way their behavior makes you feel (for example, slamming doors, cursing, making fun of them), or not letting it go (i.e. arguing with them until they agree, bringing it up several times, acting cold towards them for several hours).

The most common pattern is to be too passive initially. People take it, take it, take it. Swallow it, swallow it, swallow it. Until finally they are so mad that they overshoot the mark and become aggressive: they yell at the person, stop returning their calls, jump straight to decreasing frequency of contact, or write them off altogether. The goal of assertiveness is to get you to say something quickly before you get so angry that you overshoot the mark by becoming aggressive.

The particular technique of Assertiveness that I recommend is to tell the person the way their behavior makes you feel (and, perhaps, the behavior that you would prefer). If they are defensive, then repeat it. If they are still defensive, then let it go (i.e. be nice to them, accept their excuses, validate their emotions, apologize for your tone, move on in the conversation, and/or take a break and be nice to them the next time you see them). What’s interesting about Assertiveness, is that it doesn’t matter whether or not they agree with you. You will still feel better for getting it off your chest, and they will still change. 

The behavior (i.e. “X behavior”) should be specific, observable, and measurable. Avoid concepts and theories. If someone is always late, don’t say “When you disrespect me” or “When you prioritize your work over our friendship”. Instead, say “When you’re late.” It makes it a lot easier for them to know what you are talking about. It also eliminates most of the argumentation.

If it’s unclear what you are asking for then follow up with the preferred behavior (i.e. “Z behavior). In this case, “I’d prefer if you were within 5 minutes of our scheduled time.” In actual practice, nowadays, I often skip the preferred behavior (especially with someone I have frequent contact with), because it can come off as too controlling. Just giving them feedback on the way their behavior makes me feel is usually sufficient.

My favorite emotions to use for the “Y emotion” are “worried”, “concerned”, and “uncomfortable”. People don’t get as defensive when I use those words, and I am more likely to get a sympathetic response. Those emotions are also appropriate for a business context (i.e. “I am not comfortable with that timeline, I prefer this specific other one instead.”).

The are many reasons to let it go quickly.

One is that, when you like each other, that is when they will agree with what you’ve said. So, get out of the argument phase as quickly as possible.

A second is that, once you are nice to them, you can Mind Bomb them again! If you stay mad at them forever, you actually lose efficacy.

My favorite reason to let go is actually a behavioral one. The best way to train any “animal” (including a human!) is to administer a punishment that is brief in duration. The briefer the punishment, the more effective it is. With a human being, that means you usually have to be nice to them before they even agree with you. If you push for agreement, it will take too long. You lose efficiency, and, usually, you do unnecessary damage to the relationship.

Remember, you don’t need verbal agreement in order to get behavioral change (i.e. them hearing you and them getting upset is actually already enough to influence their behavior). Also, you don’t need verbal agreement to feel better (i.e. getting it off your chest is enough to help).

The best signs that you need to be Assertive with someone is that you are ranting about them to other people, developing evil theories to explain their behavior, and/or having fake arguments (with them) in your head. These are all clues that you need to say something directly to them, before they continue to spoil your downtime and before you blow up at them or quit the relationship. Essentially, if thinking about them is making you feel bad, then you need to get it off your chest.

This technique can also be used in tandem with Cathartic Letters for Anger. The Cathartic Letter can be used before Assertiveness (to help you figure out and clarify what you need to say), and/or after Assertiveness (to help you let it go and move on if they responded poorly).