The repertory grid method was used to determine what terminology respondents use to distinguish between different applications of genetic engineering drawn from food- related, agricultural, and medical applications. Respondents were asked to react to fifteen applications phrased in general terms, and results compared with a second study where fifteen more specific applications were used as stimuli. Both sets of data were submitted to generalized Procrustes analysis. Applications associated with animals or human genetic material were described as causing ethical concern, being (...) unnatural, harmful, and dangerous. Those involving plants or microorganisms were described as beneficial, progressive, and necessary. The results were validated in survey research, which indicated that general applications ofgenetic engineering were perceived as either positive or negative, whereas specific applications were more highly differentiated in perceptual terms. The results imply that the public debate about genetic engineering must take due account of the complexity of public concerns. (shrink)