Rod Ellis is Distinguished Professor in the Department of Applied Language Studies and Linguistics, University of Auckland. He is also a professor in the　EdD in TESOL programme at Anaheim University, USA and a visiting professor at Shanghai International Studies University (SISU) as part of China’s Chang Jiang Scholars Programme. He is currently editor of the journal Language Teaching Research. In addition to his books on second language acquisition, he has authored a number of ELT textbooks, including Impact Grammar.

Natsuko Shintani is an Assistant Professor at the National Institute of Education, Nanyang Technological University, Singapore. She obtained her PhD from the University of Auckland in 2011. She has worked as a language teacher in Japan and New Zealand, including in her own private language school for children. Her research interests　are the　role of interaction in second language acquisition, corrective feedback and meta-analysis as a research tool.