Over 40 years of archaeological investigations along the south coast of Papua New Guinea has identified a rapid succession of cultural changes during the late Holocene. The so-called ‘Papuan Hiccup’ (c. 1200–800 cal bp) is a poorly understood period of socio-economic upheaval along the coast, identified mainly from changes in archaeological ceramic styles and settlement patterns. During this period, the region-wide Early Papuan Pottery (EPP) tradition diverges into separate, localised ceramic sequences that have generic associations with local ethnographic wares. A correspondence between the timing of the Papuan Hiccup and a period of peak El Niño-Southern Oscillation (ENSO) activity implies a link between cultural and climate change. This paper explores this relationship further by examining changes in interaction networks along the south coast of Papua New Guinea, specifically focusing on chert artefacts. Chemical characterisation (portable X-Ray Fluorescence; pXRF) and technological analysis are used to map changes in lithic technology over time, including access to raw materials and technological organisation, at the site of Taurama, a prehistoric coastal village site that was occupied both prior to and after the Papuan Hiccup. Although the sample sizes are small and the interpretations necessarily circumscribed, it is argued that changes in the number of chert sources being exploited and in the intensity of core reduction at Taurama may be related to climate change in the region.