By illuminating the Earth's inland water surfaces with radar altimeter data from the ERS-1 Geodetic Mission, a global waveform analysis has shown that over 50% of echoes from even the largest lake targets are non-ocean-like in character. This paper shows that by retracking multi-mission altimeter data, height data can be obtained from the vast majority of lakes with surface area greater than 500 km2. Results from the Amazon Basin also show the great improvement in both quantity and quality of data obtained. These results graphically demonstrate that by retracking all available echoes over inland water, the potential of altimetry to measure and monitor global land surface hydrology can be realized.