The concept of an advance guard is normally associated with a military operation. Sometimes referred to as an advance unit, the main function of the advance guard is to act as a precursor for a larger unit of marching troops. The advance guard will engage in reconnaissance operations that are designed to secure a given area before the arrival of the main body of troops. This approach is often effective in minimizing the loss of life during war and other types of struggles.
While commonly associated with the military, the idea of an advance guard translates into other situations as well. For example, the idea of sending an individual or a team in advance to secure a public place is often employed with celebrities or other public figures. In this application, the advance guard has the function of making sure the location is reasonably safe for the celebrated individual who is set to arrive shortly.
Another application of the concept of an advance guard relates to the business world. Prior to contacting a corporation for a possible merger or buyout, it is not unusual for the prospective buyer to send out a team that is sometimes known as front men. Essentially, this team seeks to assess the receptivity of the targeted company to an offer of merger or buyout, including securing any data that might be helpful in the effort. The information gathered during this advance guard mission can help the prospective buyers to avoid costly mistakes that could mean killing the deal before it ever gets underway.
Even social situations can be said to employ the idea of an advance guard. People sometimes employ friends in the task of gathering data about a possible romantic interest. Doing so makes it possible to determine if the person of interest would be open to romantic advances, and thus avoid what could be an embarrassing social situation if the person is not interested.
In all incarnations of the advance guard, the idea is to pave the way for someone to follow, make the area as secure as possible, and protect the individual or group to follow from any type of unforeseen dangers. By using an advance team to reconnoiter and assess the situation, many mistakes are avoided and resources are used to better advantage.