People communicate for a variety of reasons. They communicate to share feelings, to inform, to ask, to direct, and to persuade. In the business world, the purposes of communication are the same. A few ways in which communication affects relationships in the workplace are the nature of the relationship between the people communicating, one's choice of the medium in which to communicate, and one's tone and style of communication.
There are two kinds of communication within the workplace, vertical and horizontal. Vertical communication is between people who are different levels in the hierarchy, for example, the boss communicating with the workforce or someone from the workforce communicating with the boss. Horizontal communication is peer-to-peer, equal to equal, such as two factory workers talking together or two department heads meeting. The communicator must take this into account or will harm relationships. For example, if I want to communicate with the president of my school, I will probably need to communicate through my own department head, rather than approaching the president directly. There is a chain of command in communication in many organizations, and if I breach this protocol, I am likely to find that I have offended my department head and the president will not accept anything I have to say, thus harming my relationship with both. Quite often, this protocol works in the opposite direction, with the president communicating with department heads and then the department heads communicating with the rank and file. Of course, if the president chooses to communicate directly with everyone below, he or she is free to do so, since it is, after all, the president. For horizontal communication, this is not a problem, but failure to communicate with one's peers can affect relationships, too. If the distribution department head fails to communicate a transportation problem to the production department head, the production department is going to produce products that cannot be distributed, creating problems that could have been avoided. It is usually the lack of communication that affects relationships in horizontal communications.
The medium one chooses to communicate has a great impact on relationships. Should the communication be informal and oral? Should it be an email? Should it be a memo or a notice posted on a bulletin board? One of these might be a better form than another, depending on one's purpose in communicating, and a wrong choice can affect relationships in the work setting. An example of this from a previous place of employment might serve. The director of my agency, when one person committed some sort of workplace transgression, had the habit of prominently posting a notice concerning this kind of transgression, rather than simply addressing the employee of concern in a memo. This harmed his relationship with everyone, since only one person had committed the wrong, and everyone else felt unfairly accused and annoyed. Had he singled out the person in question, he would have been communicating appropriately and would have better preserved his relationships with others. If a supervisor wants to discipline someone and does so in a casual email, rather than in a formal, disciplinary memo, the supervisor is affecting the relationship in a way that may seem positive, but that sends the message that the infraction is not really all that important, thus, while seeming to maintain a friendly relationship, sending the wrong message in the communication. As Marshall McCluhan famously observed, "The medium is the message."
Finally, one's tone and style in communication affect one's relationships. A very informal tone in a memo to one's boss may convey a sense of disrespect, for example, which is not good for one's relationship with one's boss. The use of slang and "shortcuts," such as "u" for "you," will harm relationships at work where there is an expectation of a higher and more formal standard of communication. Addressing one's supervisor as "Hey you" is not going to help one's relationship with the supervisor. Conversely, a supervisor who addresses those under him or her this way is not going to win friends and influence people.
There are other ways in which communication affects relationships at work, but attending to the relationships inherent in the communication, choosing the appropriate medium, and striking the appropriate style and tone go a long way towards affecting relationships in the workplace in a positive way.