The study of interactions between cacao (Theobroma cacao) and coconut (Cocos nucifera) in Lampung, Indonesia, examined different combinations of age, plant lay-out, planting chronology and choice of planting material under changing environmental conditions. Four coconut-cacao intercropping trials were used to assess the performance of each intercrop under limiting or non-limiting environmental conditions. In intercropping experiments with young cacao trees and young coconut palms, delayed cacao tree development and reduced yields were observed. When coconut palms were aged five years or over, coconut and cacao growth were satisfactory under virtually normal environmental conditions; death rates remained reasonable and yield percentages differed little from those of the monocultures for each crop. The performance of both plants, however, changed when water became a limiting factor.