The energy cost of subsistence activities and the daily time and energy budgets of Tatuyo women were assessed as part of a village energy flow study. The Tatuyo are swidden horticulturalists relying on bitter manioc (Manihot esculenta) as a staple crop. Except for the actual felling of new gardens, women are responsible for most of the horticultural work and food preparation. Time budgets were assessed using 24-hour activity diaries. Rates of energy expenditure in typical activities were measured by indirect calorimetry using a Max-Planck respirometer. Daily energy expenditure was calculated using these rates in conjunction with the activity diaries. Rates of energy expenditure in standard activities were moderate and broadly comparable to published values for other populations living in tropical environments. The mean daily energy expenditure was 2,133 kcal (8.9 MJ). This value is similar to that reported for other subsistence horticulturalists and close to the FAO recommendation for energy intake for moderately active individuals.