Book excerpt: The Routledge Handbook of Sociocultural Theory and Second Language Development is the first comprehensive overview of the field of sociocultural second language acquisition (SLA). In 35 chapters, each written by an expert in the area, this book offers perspectives on both the theoretical and practical sides of the field. This Handbook covers a broad range of topics, divided into several major sections, including: concepts and principles as related to second language development; concept-based instruction; dynamic assessment and other assessment based on sociocultural theory (SCT); literacy and content-based language teaching; bilingual/multilingual education; SCT and technology; and teacher education. This is the ideal resource for graduate students and researchers working in the areas of SLA and second language development.