Thorleaf Research, Inc. proposes to develop a miniaturized high pressure atmospheric sampling inlet system for sample acquisition in extreme planetary environments, such as those encountered in the lower troposphere of Venus or the atmospheres of the gas giants, Jupiter, Saturn, Uranus and Neptune. This addresses a key technology gap for planetary studies, mainly how to acquire and prepare samples for in situ analysis while meeting challenging mass, volume and power constraints. Although miniaturized mass spectrometers and other low power instruments are under development by NASA for in situ measurements, the great potential of such instrumentation for exploration of the Solar System will not be realized without complementary developments in the technology for collecting and preparing samples for analysis. Our proposed approach collects an atmospheric gas micro-sample at high pressure and transfers it into a protected low pressure environment within a small pressure housing for analysis by GC/MS, mass spectrometry or other techniques that inherently require low pressures for operation. This new technology will enable in situ measurement of the composition and key isotope ratios in high pressure planetary atmospheres down to trace levels.