The communication styles of individuals have been usefully catalogued as: passive, assertive, and aggressive. Much literature has described the consequences of each in various settings, and coached people to change styles. Although there is no eleventh commandment: THOU SHALT ALWAYS BE ASSERTIVE, it does seem the best course of action when long-term cooperation is desired (the bulk of human activity may well fit this category).
Assertiveness has been historically promoted as an effective approach to conflict resolution. However, it also has a place in maintaining positive relationships (which otherwise may fall prey to benign neglect). This communication skill can be applied in a variety of interpersonal circumstances; for example: in business settings, between lovers, by parents or teachers, and in civic activities.
Being assertive requires being clear with yourself regarding your values and the message you desire to convey. Next, the delivery of your message entails both verbal and non-verbal cues. What follows is a simplified formula for composing the verbal content, with an explanation of how your careful choice of words can foster constructive dialogue (rather than combative distancing).
There are three essential items of information about your situation that must be conveyed in order to be assertive. If you haven't provided all three of these items, you haven't completed the job of being assertive. Though there is no need to slavishly follow this script, filling in the following parantheses with the indicated content will guide you to assertive communications:
A typical mistake made during the second step is to interpret the meaning of behavior, instead of describing a specific behavior. If you complain that somebody is being "controlling," the object of your complaint may be sincerely dumbfounded, or may endorse their own attempt to "control" you. In either case, there is no compulsion for them to admit to your characterization since there is no standard for defining "controlling" behavior. Yet, if you describe a behavior that just occurred, or indicate some non-verbal cue (e.g., tone of voice) that was just delivered, most people will recognize their own performance (it helps to be timely). In fact, most people think they are entirely justified in their behavior; but they often take issue with what you think it means.
The importance of the third step is to remind yourself to take responsibility for your own problem. The problem you are seeking to solve is not the other person's behavior, but your feelings about it. They are powerless to determine your emotions. Even if someone did everything you asked of them, you could still decide that it was an insincere effort, or too little too late, and so on. Others are responsible for their behavior, and may change it if they understand the effects it has on those around them. You are responsible for your own feelings, and being assertive is one way to assume that responsibility.
You may still have a conflict of interests or desires after you deliver step three, but at least the two of you will know just exactly where you disagree. At that time, you will turn to negotiation skills or other fine points of conflict prevention or resolution. More will be posted about these later.
Please notice that the model above could just as easily be applied when you have something wonderful to say. Telling a friend you really appreciated a specific gesture of good will, and that you'd like to spend more time with him or her, can go a long way toward cementing the relationship. Assertive comments can help build intimacy.