Foreword / Rod Ellis -- Individual differences in second language acquisition : theory, research, and practice / Shaofeng Li, Phil Hiver, and Mostafa Papi -- Explicit and implicit language aptitude / Shaofeng Li -- Working memory / Zhisheng (Edward) Wen and Daniel O. Jackson -- Declarative and procedural memory as predictors of second language development / Kara Morgan-Short, Phillip Hamrick, and Michael T. Ullman -- Learning styles and strategies / Carol Griffiths -- Metacognition / Masatoshi Sato -- Motivation / Mostafa Papi and Phil Hiver -- Mindsets / Nigel Mantou Lou and Nourollah Zarrinabadi -- Goal complexes / Jeannine E. Turner, Banban Li, Yanyu Pan, Juhee Kim, and Yanyan Chen -- Willingness to communicate / Jian-E Peng -- Anxiety Peter D. MacIntyre and Lanxi Wang -- Enjoyment / Jean-Marc Dewaele -- Self-efficacy / Mark Wyatt -- Learner beliefs / Maggie (Qunyan) Zhong -- Identity / Ron Darvin and Bonny Norton -- Age / David Singleton and Simone E. Pfenninger -- Individual difference factors for second language pronunciation / Charles Nagel -- Individual difference factors for second language vocabulary / Su Kyung Kim and Stuart Webb -- Individual difference factors for second language grammar / Yuichi Suzuki -- Individual difference factors for second language pragmatics / Naoko Taguchi, Maria Kostromitina, and Holly Wheeler -- Individual difference factors for second language listening / Franz Holzknecht and Tineke Brunfaut -- Individual difference factors for second language speaking / Laura Gurzynski-Weiss -- Individual difference factors for second language reading / Eun Hee Jeon and Junko Yamashita -- Individual difference factors for second language writing / Mostafa Papi, Mohammad Ahmadian, and Lena Vasylets -- Surveys / Kata Csizér and Dávid Simon -- Narrative methods / Xuesong (Andy) Gao -- Ethnography / Peter De Costa, Matt Kessler, and Kasun Gajasinghemliyanage -- Eye-tracking / Cathy Conklin and Ana Pellicer-Sánchez -- Psychometric assessments / Lars Bokander -- Measures of implicit attitudes / Ali H. Al-Hoorie -- Methods for complexity theory in individual differences research / Phil Hiver -- Structural equation modeling and factor analysis / Yanyun Yang and Yachen Luo.