Anxiety disorders are one of the major concerns in developmental and intellectual disabilities. Since anxieties significantly impact social and adaptive functioning, it is of great urgency to better understand potential risk and protective factors. Given the crucial role of social approach, positive emotions and emotion regulation for optimal social and adaptive functioning, the goal of this project is to study these three phenomena in individuals with developmental disabilities with a particular focus on Williams syndrome (WS) and Autism Spectrum Disorder (ASD). In certain respects, WS and ASD have opposite profiles in the prevalence of anxieties (relatively high non-social anxiety in WS vs. relatively high social anxiety in ASD), as well as in social approach and positive emotions. Whereas social approach and positive emotions are high in WS, they are generally low in ASD. Moreover, while individuals with ASD have difficulties regulating emotions, little is known about emotion regulation in WS. Taking into account these opposite patterns, WS and ASD make a promising model for the study of socio-emotional phenomena as potential risk and protective factors for social and non-social anxiety. With a multi-method approach (including virtual reality), the goal of this project is to examine how these three socio-emotional phenomena relate to each other and how they are linked to social and non-social anxiety in WS and ASD, compared to a group with non-specific intellectual disability. The insights derived from this project will ultimately serve to inform interventions targeting affective disorders in developmental disabilities.