This book aims to explore the nature of code-switching. The purpose is to find out how this works and thereby inform language-teaching strategies. It focuses on Chinese / English bilinguals with special emphasis on younger students living in two linguistic worlds (Chinese and English). This book explores the determinants of code-switching between English and Chinese amongst Chinese-Australian bilingual children. It examines code-switching in relation to several grammatical structures, tonal facilitation, contextual factors, speakers social background aspects and their participation in school language programs.