In a longitudinal study on bilingual child language acquisition, Rooselaar followed four Moroccan girls in the Netherlands from approximately age 2;0 to age 3;0. The target language was either Moroccan Arabic or Dutch. Most recordings concern spontaneous speech; part is labeled as 'experimental'. Two of the girls were recorded in a day-care centre where much Dutch is spoken with the caretakers and other children. The two other girls were recorded at home with their family members. The recordings were made in the framework of a PhD thesis project, but this project was aborted after the data collection stage. Metadata on most recordings are rather extensive; partial transcripts exist of many of the recordings.