The non-immigrant visa classifications cover a broad range of visas used to enter the United States temporarily for work, pleasure or study. Some visas are considered “dual intent” ones where you may also attempt to obtain U.S. permanent residence (a “green card”) while under that classification. Most non-immigrant visas, however, require you to demonstrate a non-immigrant intent. Thus, you should be prepared to prove that you have a permanent residence in your home country that you have no intention of abandoning. The duration of time you may spend in the US can range from a few days to several years, depending on the visa category. In most situations, your spouse and unmarried children under the age of 21 may accompany you on a derivative visa.