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categories such as soils, wetlands, geology, vegetation, and demography. The objectives of 
this national data base system are to: 
• encourage and hasten the use of the Spatial Data Transfer Standard 
• provide a mechanism for improved coordination and standardization of data 
content and quality 
• provide for more consistent and compatible Federal spatial data bases 
• improve the efficiency and effectiveness of Federal agencies and others using 
Federal spatial data bases 
• inform users and potential users of digital spatial data regarding availability and 
data content 
• clarify Federal agency responsibilities for developing, maintaining, and distri 
buting spatial data bases 
Such a system will require that each agency responsible for spatial information about the 
United States be able to release its information in the standard SDTS format. The up 
dating and accuracy of a data set would remain the responsibility of the agency that has 
the mandated responsibility to collect and use that data set. The National Mapping 
Division of the Geological Survey will establish base data categories, such as hypsography, 
hydrography, transportation, and boundaries, in data files that will be obtained by the 
general public through the standard format. It is envisioned that other agencies will make 
their data available in a similar manner so that a user could acquire those data files and 
overlay them on Geological Survey base data without knowledge of the internal formats 
used by the collecting agencies. Using the standard for release of data allows each agency 
to design and use its own internal format to process spatial data and does not require 
standardization across the Federal Government on one data structure, data format, and 
hardware/software system. 
CONCLUSION 
It is clear that the time for spatial data standards is here. The availability of standards has 
many advantages to the data collector, processor, and user, particularly those who need to 
utilize data from several sources. The establishment of standard terminology will be of 
great benefit in setting a common language of definitions for users and producers of spatial 
data. A standard transfer specification will facilitate the exchange of spatial data through 
out the public and private communities and will enhance the capability for displaying and 
analyzing and integrating spatial data for a growing number of applications. The availabil 
ity of information about data quality, such as lineage, completeness, accuracy, and logical 
consistency, will help users to evaluate the fitness of the data for a particular use. The 
Spatial Data Transfer Standard provides these characteristics and offers a mechanism for 
the exchange of spatial data that is long overdue.