Recent events have brought synthetic aperture radar (SAR) interferometry into vogue—at least in some sectors of the geophysical science community. For one thing, the image of coseismic displacement associated with the Landers earthquake, recently published in Nature [Massonnet et al., 1993], coupled with the recent disastrous Northridge earthquake of January 17,1994, has created interest in the Earth science community about SAR interferometry. In particular, there is widespread appreciation that this technique can make a significant contribution to earthquake studies in California and other technically active regions. Similarly, a recent demonstration that ice stream velocity could be measured directly from space without ground control points using SAR interferometry [Goldstein et al., 1993] has caught the attention of the polar science community. However, many scientists are not familiar with SAR interferometry, and the strengths and limitations of the technique need to be explored.