Maarten Dolk is a researcher and developer at the Freudenthal Institute for science and mathematics education in the Netherlands. He is involved in the development and research of in-service and multimedia in-service materials for teachers, staff developers, and teacher educators in a number of countries. He has been a collaborating partner in Mathematics in the City since its inception and is co-author of the first three books in the Young Mathematicians at Work series.
Catherine Twomey Fosnot is the Founding Director of Mathematics in the City and former Professor of Education at The City College of the City of New York. She has twice received the "best writing" award from AERA's Constructivist SIG and she was the recipient of the "young scholar" award by Educational Communication and Technology Journal. She is the lead author of the Contexts for Learning Mathematics series as well as the Young Mathematicians at Work series.