To explore the connections between new approaches to science education and new developments in assessment, the Board on Testing and Assessment (BOTA) of the National Research Council (NRC) sponsored a two-day conference on February 22 and 23, 1997. Participants included BOTA members, other measurement experts, and educators and policymakers concerned with science education reform. The conference encouraged the exchange of ideas between those with measurement expertise and those with creative approaches to instruction and assessment.