|Multimodal stimuli have been shown to aid vocabulary learning for normally hearing (NH) populations with typical language development. Most research has, however, focused on a relatively rich context, in which the learner had to acquire a new label for a known concept. Furthermore, previous research has often dealt with learning under ideal listening circumstances. My project consisted of four studies that examined the effectiveness of augmentative signs in spoken word learning in deaf/hard-of-hearing (DHH) children and adults, children with Specific Language Impairment (SLI), and NH populations in a situation with little context (i.e., a new label for a new concept). In Study 1 DHH and NH children and children with SLI who had difficulties only in productive language use learned new words for nonsense creatures. Half of the words were presented with a sign. In Study 2 we examined the role of babble noise and Sign Language knowledge on our word learning experiment. Participants in this study were DHH and NH children. Study 3 investigated children with different types of SLI and a control group in the same word learning experiment and additional language and cognitive tasks. Study 4 combined Studies 1 and 2 with DHH and NH adult participants.