The project "Incremental Sound Change in Oslo" (ISC-Oslo) will investigate the socio-demographic origins of five ongoing phonetic changes in a post-hoc phonetic analysis of two corpora from the early 2000s. Working-class children and youth have been identified as one of the main sources of language change. Their lexical, syntactic or phonetic innovations are often disregarded by non-linguists as slang, but it has been shown that these innovations can lead to change within pre-existing dialects and even new social dialects. Due to the fact that these innovations often at first escape social monitoring, this process is referred to by Labov as "changes from below" and has been identified in a number of urban studies. The most common – yet, elusive – changes from below are phonetic. These types of changes accumulate generation after generation and result in the evolution of new dialects and languages. What is poorly understood, however, is the role of multiethnolects in this process. These are new varieties formed by the ethnically diverse speakers in Europe’s urban neighborhoods. Like many European cities, Oslo is witnessing the emergence of a new working-class sociolect spoken by the second and third generation descendants of non-western labor and refugee migrants. Multiethnolects have typically been examined within the lens of youth argot or second-language acquisition. ISC-Oslo, however, takes a different point of departure. It seeks to apply Labov’s theory on speakers of multiethnolects, who often have the same socioeconomic profiles as the innovators describes in his studies. The main focus of ISC-Oslo will be twofold. First it would develop an automatic phonetic aligner to phonetically annotate two large corpora collected in the early 2000s. Second, it would analyze the production of five innovative features that are circulating today to identify whether they originated from youth of migrant origin in the early 2000s.