Our policy experts


  • Holst, Eric Associate Vice President, Working Lands

    Areas of expertise: Conservation solutions, wildlife policy, endangered species, agriculture, mitigation, forestry

    Office: Sacramento, California

  • Holstein, Elgie Senior Director for Strategic Planning

    Areas of expertise: Climate change, Land, Water & Wildlife programs, rivers and deltas, energy policy

    Office: Washington, D.C.

  • Hull, Hillary Senior Manager, Research & Analytics

    Areas of expertise: North American oil and gas, energy, and air policy; research and data analytics

    Office: San Francisco

  • Kaiser, Dan Senior Manager, California Habitat Markets

    Areas of expertise: Environmental markets, agriculture sustainability, water quality, non-point source pollution

    Office: San Francisco

  • Kalesi, Poppy Director, Global Energy

    Areas of expertise: EU energy policy; European gas markets; oil and gas industry innovation

    Office: Remote

  • Karas, Natalie Lead Counsel, Energy Markets & Utility Regulation

    Areas of expertise: Natural gas and electricity market design, natural gas policy, utility regulation

    Office: Washington, D.C.

  • Kelly, David Senior Manager, North Carolina Political Affairs

    Areas of expertise: Clean energy, energy efficiency, environmental markets, agricultural sustainability, shale gas development and production, and public policy

    Office: Raleigh, North Carolina

  • Keohane, Nathaniel Senior Vice President, Climate

    Areas of expertise: Carbon markets, economics, climate change, U.S. and global climate and energy policy

    Office: New York City

  • Kiely, Pam Sr. Director of Regulatory Strategy

    Areas of expertise:

    Office: Boulder, Colorado

  • Kizzier, Kelley Associate Vice President for International Climate

    Areas of expertise:

    Office: Remote

  • Koehler, Larissa Senior Attorney, Energy

    Areas of expertise: California energy law and policy, electric transportation, UK transport and air quality policy

    Office: San Francisco

  • Kritee, Kritee Senior Scientist

    Areas of expertise: Climate smart agriculture, Soil carbon, Soil Health, Rice, Methane and nitrous oxide emissions, Nitrogen & Water use efficiency, Environmental microbiology, Stable isotope biogeochemistry, and Mercury pollution

    Office: Boulder, Colorado

  • Kroopf, Sara Manager, Supply Chain

    Areas of expertise: Agricultural economics, environmental markets, sustainable agricultural systems, corporate social responsibility, scope 3 emissions, agricultural emissions accounting, agricultural carbon markets

    Office: Remote

  • Kuzdas, Christopher Project Manager, Water Program

    Areas of expertise: Water management and governance; public policy; decision support; social-ecological systems; risk management; rural development and planning

    Office: Remote

  • Levitan, Ben Attorney, Legal and Regulatory

    Areas of expertise: federal environmental and energy regulation, Clean Air Act, climate pollution from the power sector

    Office: Washington, D.C.

  • Leyden, Colin Senior Manager, Regulatory & Legislative Affairs

    Areas of expertise: Oil and gas, energy policy, ground-level ozone and air quality

    Office: Austin, Texas

  • Lujan, Breanna Project Manager, Forest and Climate Policy

    Areas of expertise: Zero-deforestation supply chain commitments, REDD+, climate change, deforestation mitigation in the Amazon, land sector issues

    Office: Europe

  • Mahoney, Melissa Manager, Pacific Fisheries Policy

    Areas of expertise: Fisheries Management/policy, human dimensions of fisheries, collaborative fisheries research, electronic monitoring, visual communications

    Office: Remote

  • Margolis, Josh Managing Director, Environmental Markets, Climate Program

    Areas of expertise: Market-based and environmental policy instruments, environmental credit trading, environmental permitting.

    Office: San Francisco

  • Mathers, Jason Director, Vehicles & Freight Strategy

    Areas of expertise: Freight electrification, fleet vehicles, green supply chain

    Office: Boston