This edited collection contains 13 selected papers presented at the Romance Turn IV conference, which was held at Universite Francois Rabelais, Tours, France, in 2010. The volume reflects the diversity of interests of the contributors, not only in the learning contexts investigated (first language acquisition, typical or impaired, and bilingualism), but also in the linguistic properties being explored, in both syntax and phonology, and the languages under examination (work not only on Romance languages such as French, Italian, Brazilian Portuguese, European Portuguese, Romanian, and Spanish,...