Home / USGC Global Presence / U.S. Headquarters OfficeU.S. Headquarters Office Executive Team Ryan LeGrand President and CEO Cary Sifferath Vice President Cierra Walker Executive AssistantEthanol and Economics Mackenzie Boubin Director of Global Ethanol Export Development Joana Hassan Manager of Global Ethanol Programs Linda Schmid Manager of Ethanol Policy and Sustainability Samantha Redfern Global Ethanol Program CoordinatorGlobal Strategies Kurt Shultz Senior Director of Global Strategies Sadie Marks Manager of Global Strategies and Trade Alexander Grabois Manager of Global Strategies and Trade Jace Hefner Manager of Global Trade Sam Clemence Global Strategies CoordinatorGlobal Programs Stella Qian Director of Global Programs Administration Sierra Richey Manager of Global Programs Caleb Floss Manager of Global Programs Lucas Rudy Global Programs CoordinatorTrade Policy and Biotechnology Andrew Brandt Director of Trade Policy Carlos Suárez Manager of Sustainability, Policy and Innovation Dylan Biggs Trade Policy CoordinatorCommunications Bryan Jernigan Director of Communications Emily Sutton Manager of Communications Will Margerum Communications CoordinatorIndustry Relations Ellen Zimmerman Director of Industry Relations Teresa Myers Senior Meetings Manager Emma Freebairn Manager of Industry Relations Administration Rebecca Williams Manager of Industry Relations Emily Schneider Industry Relations CoordinatorFinance Addis Tilahun Director of Finance Hiwot Arnold Manager of Domestic Accounting Donna Braswell Senior Manager of Overseas Accounting Mevis Clarck Accounts Payable Manager Milla Par Manager of International Accounting Tatiana Ciobanu Manager of Program FundingAdministration Helen Elmore Director of Administration and Operations Yeshake "Isaac" Assefa IT Manager