This scoping study aims to develop research strategies for optimising concurrent production of coffee and food crops in integrated systems on smallholder farms. Coffee accounts for about 30% of Papua New Guinea's export earnings, and smallholders produce 90%. Coffee is the main source of cash income in highland areas; sweet potato and other crops are grown for food. Demographic and economic forces threaten the sustainability of these mixed production systems; other cash crops and staple food crops compete with coffee for scarce resources, including land, crop nutrients and labour. This Small Research Activity aims to understand these trade-offs and identify needs for research and extension to make these coffee-based systems more sustainable, productive and profitable.