The Sl'colld International Symposium on Basic Environmental Problems of Man in Space was held 14-18 June 1965 at Unesco House, Paris. It was or- ganized by thf' International Astronautical Federation and the International Academy of Astronautics with the support and cooperation of Unesco, the International Atomic EUl'rgy Agency, the World Health Organization, the World MeteOl'ological Ol'ganization. and the International Telecommunication Union. Thc Sympmliulll was devotcd to four main problem areas, viz. (1) ecophysi- ology, (2) psychophysiology and engineering psychology, (3) special man- machine probh ms. and (4-) biot, echnology. A total of 30 papers-all by special invitation--wpl'(' PI'PRf'lltl'd during \) half-day working sessions. Eight ofthe papers were from the P, S, A" S fl'Olll the U, S, S, R., and 14from other countries. The pres- entations includcd foUl', !pneral review papers. The working languages were English, Russian. ami Fl't'Ilch, This volul1H' contaiwl aH the papers of the Symposium and also reports the discussionK foHowing individual papers. Papers in the Russian language appeal' in full also in English, Abstracts appear in all three languages, trans- lations being;upplipd by eOUl'tesy of Unesco. For the reporting of discussions the following sysü'lll wal' used, Each person asking a question or making a comment from the flool' was given a "question and answer" form immediately after he had finished sppaking. Thc questioner and the session speaker were asked to writp down thpir qtlPstions. answers or comments at their earliest conwnience and to "PÜII'1l thp completed form the same day if possible.