Approximately 5% of the Caucasian North European and North American populations are carriers of the gene defect causing cystic fibrosis (CF). Since the CF gene was isolated in 1989 and the common mutations identified, there has been debate as to whether community-wide screening for CF carriers should be offered. Pilot studies and new discussions are leading to a consensus that screening is now possible and will not lead to undue anxiety, but there is still no agreement as to cost, or how it will be used by those screening positive.