In the following text an attempt has been made to condense the main points of the MEIPIC-2 conference, to correlate certain results scattered over different contributions, to give some comments, suggestions for future work and a few historical ref. points. Those contributions which have been less discussed, reflect simply the incompentence of the writer and not a ranking. The names in brackets without indication of the year represent authors of these Proceeding (see AUTHOR INDEX). The other refs. with nos. are given at the end of this Introduction. The subdivision in Sections 01. to 10. is a pragmatic one, implying many crossovers.