Flows of resource subsidies, such as terrestrial leaf litter to streams and adult aquatic insects to riparian predators, are examples of important links between adjacent ecosystems.  The importance of these cross-ecosystem flows from donor systems to the recipient consumers is increasingly recognised.  We have experimentally manipulated these flows (leaf litter, terrestrial invertebrates, and adult aquatic insects to riparian areas) to test the magnitude of these effects in small streams and their riparian areas.  Streams are highly dependent upon such subsidies and the value of the subsidy is further affected by its retention and pathways of its use.  The nature of the subsidy and its timing are also important details that need further study, along with the evolution of life cycle timing (modelling) and interception strategies by recipient populations.  Experiments typically indicate rapid growth or demographic responses by consumers, indicating these populations are resource limited or at levels of incipient population limitation, and can capitalize on short-term resource pulses. Responses to the specific nature of the subsidies (species or age class of litter or invertebrates) needs to be further tested.  Demonstration of the importance of such subsidies to population ecology and to ecosystem function has largely come from aquatic systems.