discrimination of rock types and detection of hydrothermally altered areas 
(Rowan, et al, 1974). Statistical classification of digital, multidate Landsat 
data has been shown to be a promising tool in forest and range inventories, in 
land cover mapping and change detection, and in prediction of worldwide agri- 
cultural crop production (Rohde, 1978; Ellefsen & Peruzzi, 1976; MacDonald, et 
al, 1977). In the 70's we have made substantial progress in the storage, re- 
trieval, and dissemination of remotely sensed data, and in the variety and 
sophistication of the applications of these data. 
Experiences of the 70's 
Equally noteworthy are the lessons we have learned in the six years since the 
launch of Landsat-1. Some selected examples are: 
1. Acceptance of a new technology takes time. 
2. Technology transfer is best achieved through personal interaction with 
and participation by the user. 
3. Further improvements to the existing and planned systems and analysis 
procedures are necessary to obtain the maximum utility of the data. 
4. Designation of organizational responsibilities and a clear commitment 
to continue data availability are required to speed operational use. 
Item #1 requires little explanation to anyone who has attempted to incorporate 
the Landsat and related technologies into the routine day-to-day activities of 
a major user agency, such as the Department of the Interior. In most cases, we 
have grossly underestimated the time it takes to (1) prove the scientific 
validity of the technology to a particular application; (2) test the applica- 
tion under semioperational conditions for a period of time to determine cost 
and reliability; (3) train agency personnel in the use of the techniques (and 
install equipment for data analysis, if appropriate); and (4) overcome the 
institutional resistance to new technology in general. 
For example, we have attempted with limited success to document the cost/benefits 
of the Landsat technology during the past six years, whereas experience indicates 
that a more reasonable time period for evaluation might be 15-20 years (see 
Table 2). We share the view that systems such as Landsat will provide continued 
expansion of a common, worldwide data base for use by all nations, but we must be 
patient, for the vast majority of the Earth's inhabitants have never used such 
data before and it will take a great deal of time and work before the value of 
the data is widely recognized. 
One way to shorten the period between the research phase and routine application 
of advanced technology is to recognize the needs and vital role of the prospec- 
tive user (Item #2). Thorley and Hood (1977) have commented on some common ele- 
ments that apparently enhance the successful application of Landsat data: 
"Examination of the applications of Landsat data which have achieved operational 
or near operational use reveals certain common elements, such as the following: