Preface; Introduction; 1. On heritage speakers as native speakers; 2. Structural changes in heritage language grammars; 3. Differential Object Marking; 4. Language change and the acquisition of Differential Object Marking; 5. The vulnerability of Differential Object Marking in three heritage languages; 6. Differential Object Marking in Spanish as a heritage language; 7. Differential Object Marking in Hindi as a heritage language; 8. Differential Object Marking and clitic doubling in Romanian as a heritage language; 9. Comparing the three heritage languages; 10. Intergenerational transmission.