Sweetpotato is the most important food crop in the Highlands of Papua New Guinea (PNG). In recent years, sweetpotato has become a cash crop for smallholder farmers driven by the need to generate income in a market economy. Marketing opportunities exist for Highland sweetpotato, especially in coastal markets, because of income growth and urbanisation. Despite this , long distance sweetpotato marketing has been problematic. The objective of this research was to identify socio - economic constraints to, and opportunities for, improving the marketing efficiency of the long distance sweetpotato value chain in PNG. The results from the value chain analysis suggested that although there was a demand for high quality Highland sweetpotato in coastal markets, the long distance sweetpotato value chain was underdeveloped . This was due to several constraints : lack of access to sup port services (credit , extension and market information); poor infrastructure (roads and the transport system and storage and market facilities) ; inadequate postharvest management ; lack of business skills , financial literacy and marketing planning ; unclear price signals; lack of trust among chain players , uncoordinated value chain activities; and declining demand. The main conclusion was that to transition from subsistence farming to semi - commercial/commercial farming, s mallholder farmers need to become more market - oriented and better equipped with business skills . Furthermore, they need to be prepared to change their current marketing and postharvest practices in order to supply high quality products to the right markets at competitive prices. Government also has a key role to play in terms of providing an appropriate enabling environment , including a reliable transport system , business development services and a locally appropriate pricing and grading system . This environment is necessary to support the effort of farmers in adopting improved marketing and postharvest practices.