Speech produced by children in the initial stages of development does generally not uphold as many phonetic distinctions as speech sounds produced by adults. A child's productions of different target words may therefore have similar acoustic properties and result in homonyms being perceived by the adult observer. This study presents a longitudional investigation into the development of place of articulation from non‐distinctive to distinctive productions in word‐initial obstruents produced by 22 Swedish children (aged 18 ‐ 48 months). The data was collected through monthly recordings, approximatelly one year per child. The acoustic correlates analysed were spectral diffuseness, spectral skewness and spectral tilt for plosives and spectral skewness, spectral kurtosis, spectral variance and F2 onset frequency for fricatives. The results show a developmental trend in spectral skewness that is indicative of a increasing number of acquired phonetic contrasts. Spectral tilt change, F2 onset frequency, spectral mean and spectral variance provide evicence of within‐category refinement wich is argued to be caused primarilly by advancements in motor control.