To the best of the authors’ knowledge, simultaneous translation has not been the subject of any experimental studies. This is one of the reasons why in the present investigation, the authors have limited their selves to a relatively preliminary description of some of its aspects. The authors have considered a number of quantitative values, particularly those involving interpreter’s output compared with that of speakers or a written translation. Other values are of more qualitative importance insofar as they enable the degree of correspondence, and hence the accuracy, of the translation to be assessed. However, the authors have focused on considering the phenomena in question in terms of how they occur over time, examining the speaker’s activity relative to that of the interpreter. It is quite obvious that the term ‘simultaneous’ is an approximation only, covering a fairly complex process whose variations must be presented by the analysis.