Speaking up in instances of conflict can be difficult, especially if you’re shy, lacking confidence, or come from a culture where it is inappropriate to speak up. But there is hope for the chronically unassertive among us. Simply use an “assertiveness formula.” There are three steps to an assertiveness formula. First, start with a short, simple, objective statement about the other person’s behavior — what you’d want to see changed. Second, describe the negative effect that this behavior has had on you. Third, end with a feelings statement. An example of a feelings statement might be “I feel marginalized.” Putting it all together, you have something like this: “When you continually interrupt me during meetings, I don’t get a chance to voice my opinion and I feel marginalized.” A well-crafted assertiveness message can be effective on the spot, but it can also be something you hone and craft in preparation for an upcoming conversation.

In the workplace, we all run into conflict. Many of us would love to speak up and assert ourselves to correct it. And, in a perfect world, it would be easy. You could finally tell that colleague who keeps interrupting you exactly how you feel. You could give him a piece of your mind, releasing the frustration and anger that’s been gnawing at you for months. You could finally express that part of you that feels so underappreciated and marginalized.

But speaking up can be difficult — and sometimes overwhelming — especially if you are shy, lack confidence, or come from a culture where it is inappropriate to speak up. It can feel pushy and overly aggressive to be assertive, especially if you’re timid or hate conflict. It can also feel awkward and unnatural, not least if you’re more inclined to voice your frustrations and discontent in an indirect or passive manner.

But there is hope for the chronically unassertive among us. Fears about speaking up are hard but not impossible to overcome. Voicing your frustration with an “assertiveness formula” can help.

I first learned about the idea of an assertiveness formula many years ago, reading the book People Skills, by Robert Bolton. Although Bolton applied his formula to instances of everyday life (for example, discussing household chores), I found it equally appropriate for the workplace. Over time, I’ve developed my own three-part version of it in my teaching and training.

Start with a short, simple, objective statement about the other person’s behavior — what you’d like to see changed. For example: “When you interrupt me during meetings” or “When you take sole credit for the work we’ve done collaboratively.” Your goal here is to get the other person’s attention and, in doing so, minimize their defensiveness. The statement should be short, to the point, and evenhanded and unemotional enough that they can hear your message and not immediately disagree or disengage. Describe the negative effect that this behavior has had on you. Explain why the person’s behavior is causing a problem. For example, if the first part of the formula is “When you continually interrupt me during meetings,” you might then add, “I don’t get a chance to voice my opinion.” Or, for “When you take sole credit for the work we’ve done collaboratively,” you’d add, “I don’t have a chance to highlight my role and contribution.” The goal here is to build a cause-and-effect logic, linking an objective statement of their behavior to the impact that the behavior has had on you. End with a feelings statement. Here, you want to indicate how their offending behavior has not only negatively impacted your actions but also hurt your feelings. An example of a feelings statement might be “I feel marginalized” or “I feel underappreciated.” While the other person may feel surprised— and even uncomfortable — to hear this, it’s hard to refute a person’s feelings. Adding this element makes the assertiveness message as a whole that much more powerful.

Putting it all together, you have something like this: “When you continually interrupt me during meetings, I don’t get a chance to voice my opinion, and I feel marginalized.”

A well-crafted assertiveness message can be effective on the spot, if you have the emotional wherewithal to deliver it. But it can also be something you hone and craft in preparation for an upcoming conversation, especially if you don’t feel particularly practiced at the craft or if you’re anticipating a defensive reaction from the other person.

Of course, even with a formula in hand, assertiveness isn’t always easy. It’s quite possible that the recipient of your message will react negatively, so you’ll want to meet any response with a calm, steady, and confident presence. You’ll also want to accumulate as much evidence as possible to support the first part of your message — the statement about the other person’s offending behavior. Your goal is to provide enough clarity and specificity about this behavior that your statement impossible to refute. What also helps is demonstrating a pattern of behavior over time, which might require you to keep a diary of instances when you’ve felt hurt, undermined, or offended by the person’s actions. Don’t use this record as an opportunity to harp on your colleague for the many times you felt they were at fault; use it only as backup material if your counterpart refutes you and needs convincing. This evidence will be key for increasing the likelihood that your message will be heard and ultimately have the intended effect on the recipient.

Keep in mind that there is no one-size-fits-all version of the message. You can tweak it to your own style to make the message feel as authentic as possible. For instance, I’ve interviewed one manager who liked to pace up and down the hallway a few times, with what she called an “executive-style” walk, to get up the courage to confront her colleague. Someone else made sure not to use “qualifiers” in her speech (“I’m really sorry, but…” or “Maybe it’s just me, but…”), and instead aimed to get right to the point (“I’m not comfortable with…”). Others drew on their convictions — the reasons they were speaking up — to give them the courage. For example, someone who wants to teach their children to stand up to others used that conviction as a guiding purpose for speaking up themselves. The point is that you have more power than you think to craft a personalized way to speak out, one that works for you.

In the end, speaking up is genuinely hard for many of us. And the results are far from guaranteed. The other person may respond in a positive way immediately; they might respond positively and productively but with a significant delay; or they might not change at all. But for you, getting up the courage to voice your frustrations in the first place can be a significant win.