One of the basic aims of working group IV-9 was to 
obtain information about accuracy of medium and large scale 
maps required in different countries according to their spe- 
cific conditions. Besides other valuable data 48 from 63 
cooperating organizations reported permissible planimetric 
  
and altimetric errors for the supposed image scales, which 
had been fixed according to the needs of the map users. In 
this way one of our aims was resched. : 6) 
The summaries to individual chapters are a very rich 
statistical material about influence of specific conditions 
upon the required map accuracy. They make it possible to 
examine from the economical as well as technical point of 
view how far we make use of photogrammetry in mapping and 
how it would be possible to make it better by change of some 
parameters. 
We suppose, that information extracted from the 
questionnaires will be a basic material for starting closer 
international contacts and exchange of opinions and experien- 
ces. We hope, that all iSP commissions will pay their attieniiol 
to suggestions, as well as problens that will result from the § 
  
international contacts as they will from further prograunes. 
It is obvious according to information about present 
problems in different countries and according to problems pro- 
posed for investigation in next years that an international 
coordination of research in the ISP would be very reasonable 
as well as closer experience and information exchange. It 
seems to be the best way for map producers to get all inior- 
mation they need about factors affecting accuracy and econo- 
my of photogrammetry.