The invention relates to neutralizing antibodies, and antibody fragments thereof, having high potency in neutralizing hCMV, wherein said antibodies and antibody fragments are specific for one, or a combination of two or more, hCMV gene UL products. The invention also relates to immortalized B cells that produce, and to epitopes that bind to, such antibodies and antibody fragments. In addition, the invention relates to the use of the antibodies, antibody fragments, and epitopes in screening methods as well as in the diagnosis, prevention, and therapy of disease.