Let’s assume you know what you’re doing.

You know the risks of writing in anger. You are aware that, unlike in-person conversations, written communication does not allow you to respond to body language or to modify your tone and approach as you go. You know that whatever you write "stays indelibly clear for an indefinite period," to quote author David Ewing, that over time your words will lose none of their immediacy.

But this particular situation is exceptional. Despite the insufficiency and the rigidity of the written word, you decide to express your anger in writing.

Now, given your thoughtful, rational nature, you don’t just sit down to your keyboard and blast away; you carefully consider your purpose and how best to achieve it.

Recalling your training as a skilled communicator, you follow this five-part formula:

Depending on your strategy, you open abruptly, or perhaps you begin somewhat indirectly, with a words such as, "I’m sorry to complain, but . . ." Either way, you state your purpose clearly and unambiguously. Your language is noninflammatory. Your tone is firm but respectful.

You describe the problem, again using noninflammatory language. You focus on actions and consequences rather than on personality and character. You avoid questioning your reader’s intelligence, competence, or ethics, unless such questioning or personal evaluation is the main point of your complaint.

If the problem is cumulative, you provide a specific, detailed, accurate record of occurrences. If the problem relates to a single event, you concentrate on the issue at hand rather than provide a laundry list of incidental grievances.

Depending on your rhetorical strategy, you acknowledge your reader’s position. You point out, however, that it is invalid in this situation.

You are clear and specific about the action you want your reader to take. You know that your request is reasonable and within your reader’s power or capability. If your purpose is to present an ultimatum, you end your letter with words to this effect: "If this problem is not resolved, I will have no recourse but to . . ." The consequences you threaten are relevant and proportionate to the problem.

If you hope to preserve good relations with your reader, you conclude on a hopeful note. You express your desire to put the matter behind you. You emphasize the mutual benefits of finding a satisfactory solution. Perhaps you allude to your personal regard for your reader or to the satisfactory nature of your previous relationship.

Now, you’ve written your letter, but you resist the urge to send it immediately. You know one negative word carries the weight of 10 positive ones, and you know you will be more sensitive to your tone if you reread your text after you have let it go cold.

Finally, you send your letter. And what happens?

If you’re lucky, your reader responds with an apology and agrees to take the desired action. Even if your reader has said something that annoys or angers you, you write a letter thanking your reader for resolving the issue, and you disregard everything else.

But what usually happens?

You receive an angry letter in return. Now what?

Here’s my advice:

2. Reread the other person’s letter the next day. Chances are, it won’t sound as angry and unreasonable as it did when you first read it.

3. If your reader has offered a compromise, consider accepting it.