A fee may be charged for issuing a visa; these are typically also reciprocal, so if country A charges country B's citizens 50 USD for a visa, country B will often also charge the same amount for country A's visitors. The fee charged may also be at the discretion of each embassy. A similar reciprocity often applies to the duration of the visa (the period in which one is permitted to request entry of the country) and the number of entries one can attempt with the visa. Expedited processing of the visa application for some countries will generally incur additional charges.