Citrus greening disease (CG), also known as Huanglongbing (HLB), is generally acknowledged as the most destructive citrus disease known, eclipsing the worst citrus tristeza virus outbreaks in the early 20th century. This article will describe CG and its vector and describe its effects on citrus trees and the citrus industry in the United States. Comparisons of disease spread in tropical and sub-tropical areas such as Florida with spread in the Mediterranean and desert climactic zones, which are similar to those found in the Middle East and North Africa (MENA) will be made. Additionally, successful methods used to slow the spread of the disease in the USA will be presented and some suggestions will be made that may slow the movement of CG into the MENA and reduce its impact upon arrival.