We review and integrate studies on carbon dynamics from forest sites across Amazonia, focussing in particular on the LBA flux tower sites at Manaus K34, Tapajos km 67, and Caxiuana. We integrate data from flux tower studies, tree and coarse wood inventories, litterfall and fine root turnover studies, and measurements of the respiration of soil, stems and leaves. The components of above- and below-ground productivity are explored and compared, and cross-checked for closure of the interval carbon budgets. At all sites respiration rates are much greater than productivity in leaves, stems and roots, confirming observations of low carbon use efficiency. Data from these sites are compared with new observations of carbon cycling in western Amazonia lowland forests (Peru) and initial observations from an elevation transect in the Peruvian Andes. We conclude by speculating on the causes and variability of carbon allocation patterns across Amazonian forests.