Definition of the problem: This article describes the communication structure concerning the problems of genetic engineering, in-vitro fertilization and the current debate about „genetic advisory”. Arguments: Proceeding from the social systems theory, two observation types are discriminated: 1st and 2nd orders, which occur here as critical and affirmative positions. The first term refers to specific operations of the social system of medicine, the second to communication of social movements. Neither perspective can deliver total rationality or unity, and the two positions (...) cannot be put together as one rational model. They have to be put into debate structures in order to learn from each other by reciprocal observations. Conclusion: Every kind of observation, taken in a communicative frame like this one, delivers a limited, but necessary contribution to the debate. System rationality will be possible only by coupling asymmetrical observations. This goal will, however, can only be reached, if the communication proceeds in a controversy based mode. This way, the difference between critical and affirmative positions cannot be „solved” but it can be used for further recognition. (shrink)