Regina Obe is a co-principal of Paragon Corporation, a database consulting company based in Boston. She has over 15 years of professional experience in various programming languages and database systems, with special focus on spatial databases. She is a member of the PostGIS steering committee and the PostGIS core development team. Regina holds a BS degree in mechanical engineering from the Massachusetts Institute of Technology. She co-authored PostGIS in Action. Leo Hsu is a co-principal of Paragon Corporation, a database consulting company based in Boston. He has over 15 years of professional experience developing and thinking about databases for organizations large and small. Leo holds an MS degree in engineering of economic systems from Stanford University and BS degrees in mechanical engineering and economics from the Massachusetts Institute of Technology. He co-authored PostGIS in Action.