This thesis examines possible contact effects in the segmental phonology in an idiolect of Swedish Romani. From data gathered from one speaker of Swedish Romani I describe the phonology on a segmental level and then compare this with the phonology of its progenitor, Proto-Northwestern Romani. The traces of interference could in almost every case be explained as features gained from contact with Swedish. When features were judged to have entered Swedish Romani from a different language, intense contact with Swedish could possible explain why these features have remained in Swedish Romani.