Bilingual cases are now commonplace in many Speech Language Pathology (SLP) clinics. For example, in Australia, over 23% of the population speak a language other than English at home (Australian Bureau of Statistics, 2012). Clinicians who work with developmental speech sound disorders (SSD) have on average nearly 10% of children on their caseload who "speak English as a second or other language" (McLeod & Baker, 2014). However, evidence-based guidelines for the management of such cases reflect the small research evidence base (e.g., International Expert Panel on Multilingual Children's Speech, 2012). A recent systematic review investigating the influence of bilingualism on speech production (Hambly et al., 2013) concluded that there are qualitative differences in the phonological development of typically developing bilingual children compared to their monolingual peers ( e.g., more likely to use atypical speech substitutions and omissions). Only 13 of the studies reviewed described bilingual children with SSD. The review identified a number of factors that account for individual variation in bilingual children including "the types of languages spoken, the length and frequency of exposure to both languages and the child's age and broader speech processing and memory skills" (Hambly et al., 2013, p. 14). This chapter presents a case study explaining how these factors influenced clinical assessment and intervention decisions for Kim, a child with unintelligible English speech who first acquired Vietnamese and then Australian-English at school.