National Research Council (NRC) Committee- the Space Studies Board

RIDGE2000 Steering Committee

Subject Editor- Geobiology Journal

TIGR Tree of Life Scientific Advisory Board

Task Group to Assess Mars Science and Mission Priorities-Lunar Space Studies Board's Committee on Planerary and Lunar exploration (COMPLEX)

Invited participant in Dahlem Workshop on "Energy and mass transfer in marine hydrothermal systems"

Invited for EU-US Workshop on Research Infrastructures for Life Sciences, Valencia, Spain

Member to InterRidge Scientific Committee

Editorial Board Member for journal "Extremophiles"

Editorial Board Member for journal "Microbial Ecology"

Associated member of Bergey's Manual Trust

Member of deep-sea submergence scientific committee (DESSC)

NEPTUNE Ridge Crest Science Working Group

Invited participant and organizing committee member to the National Academy of Sciences First Annual US-China Frontiers of Science Meeting, organizer of sessions "The Chemistry of the Origin of Life" and "The Age of the Universe"

Invited participant - NRC and Space Studies Board's Task Group on the "Preventing the Forward Contamination of Europa"

Invited participant - NASA Workshop-Laboratory Instrumentation for Analysis of Returned Samples-LIFARS

NRC Task Group on Issues in Sample Return from Mars