The methodological grid we are developing here has to be considered as a proposal enlightened by some applied research in the field on information TA and, especially in the field of medical informatics. We propose here a general TA approach which borrows many features from more known TA methods. The core of our methodological proposal - which, as explained in chapter 2, cannot be dissociated from the CTA movement - is the controversies analysis. By developing this method, we are searching a better understanding of the real risks and advantages linked to a technology, but also the settlement of solid foundations in order to work out a future consensus around a new technology. This means that the paper will focus on the social construct of technologies. We have to see the problems not in terms of social adjustment, but rather in terms of taking into account the other dimensions of the innovation processes. Following the theoretical presentation of the controversies analysis method, we present a concrete case study concerning the development of Computerised Health Cards in Europe during the late eighties.