This dissertation reports the findings of five studies investigating he language-cognition interface in various clinical populations. Due to the interdisciplinary nature of the topic, an integrative approach is applied to this research, claiming that both precise syntactic principles and more general cognitive mechanisms can account for phenomena observed in typical and atypical language development. Specifically, it is argued that the acquisition difficulties associated with certain structures in which an object has been moved are due to an interaction between formal syntactic properties, such as intervention effects within a featural Relativized Minimality framework, and processing limitations in attention and working memory. According to this line of reasoning, both domain-specific and domain-general skills have a role to play in the syntactic development of certain clinical populations, a hypothesis which is tested and validated via two cross-sectional studies, two working memory training studies and one priming study.