This study validates cloud top pressure measurements from the GOES-8 sounder. Data from March 2000 to April 2001 from the Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) program Cloud and Radiation Testbed (CART) site near Lamont, OK were used as the validation source. This includes cloud top height derived from a ground-based combination Micropulse Lidar/Millimeter Cloud Radar (MPL/MMCR). Hourly cloud top pressure measurements from the sounder were first converted to height using computer model output. These sounder cloud height measurements were compared to time averaged MPL/MMCR cloud top heights. The data were filtered to make sure only single layer cloud decks were compared. After eliminating multiple cloud levels, the comparison shows correlation between the two independent measurements.