Abstract: Since 2003, the Eastern cherry fruit fly, Rhagoletis cingulata (Loew), an introduced Tephritid fly from North America, has been observed in Germany in increasing abundance. We present an overview of the increase in distribution and discuss the consequences for management programs for sour cherry (Prunus cerasus). Following the identification of a single female in a malaise trap in Rhineland-Palatinate (central Rhine region) in 1999, a trapping program was conducted near the original host site and in several cherry growing regions from 2002 onward. In 2003, a few specimens of R. cingulata were reported on yellow traps in cherry orchards in the Rhineland-Palatinate area. Since 2004, the number of individuals found in Rhineland-Palatinate cherry growing regions increased considerably and the species was also found in other Federal states. At the present time, the species has been collected from nearly all cherry-growing regions of Germany. In Germany, R. cingulata is emerging 3-4 weeks later than does the European cherry fruit fly, R. cerasi, and mainly attacks sour cherries. In some years and locations, the Eastern cherry fruit fly has caused more than 20 % damage in sour cherries, whereas infestation due to R. cerasi in sour cherries usually is of low importance. The species status has been confirmed by Dr. Allen Norrbom, Systematic Entomology Laboratory, Agricultural Research Service, US Department of Agriculture, USA.