Advances in genetic research make it possible to identify carriers of a growing number of genetic diseases. The World Health Organization (WHO) published several preconditions for community carrier screening. This paper aims to present some of the dilemmas about screening in Israel and the difficulties in following the WHO's helpful criteria. Some of the genetic diseases that are rare in the world are relatively common among several communities in Israel, and one of the dilemmas is for which of them screening is justified. Consensus exists among professionals and among the public about screening for a severe disease like Tay-Sachs, but the justification for screening for a disease with a widely variable expression, like Gaucher disease, is debatable. Another dilemma is whether to offer screening to the general population when the options to solve the problem are still not clear, as is the case of screening for carriers of BRCA1 and BRCA2. The author also explains why geneticists in Israel cooperate with a screening program in the ultra-orthodox community, although it is done according to unusual rules.