There is widespread agreement that certain non-creole language varieties are structurally quite different from the European languages out of which they grew; however, until now, linguists have found difficulty in accounting for either their genesis or their synchronic structure. This study argues that the transmission of source languages from native to non-native speakers led to ‘partial restructuring’, whereby some of the source languages’ morphosyntax was retained, but a significant number of substrate and interlanguage features were also introduced. Comparing languages such as African-American English, Afrikaans and Brazilian Vernacular Portuguese, John Holm identifies the linguistic processes that lead to partial restructuring, bringing into focus a key span on the continuum of contact-induced language change which has not previously been analysed. Informed by the first systematic comparison of the social and linguistic facts in the development of these languages, this book will be welcomed by students of contact linguistics, sociolinguistics and anthropology.