Objective: This study assessed the potential influence of biofield treatment on cultured human cancer cells and whether such influence was affected by varying the duration of the treatment (dose) or the distance between the biofield practitioner and the target cells. Design: Biofield treatment dosage was assessed from a short distance (0.25 meters) in three independent experiments involving 1, 2, or 5 treatments, along with another set of three independent and comparable mock experiments. Biofield treatment distance was assessed at 0.25, 25, and * 2000 meters involving two treatments in three independent experiments along with another set of three mock experiments. Intervention: Biofield treatments were delivered by a highly acclaimed biofield practitioner with the intention of diminishing growth of the cells or inducing cancer-cell death. Outcome measure: Cell viability was quantified 20 hours after treatments, using a spectrophotometric assay for live-cell counting. The dependent measure for each experiment was the log ratio of the cell viability values of treated samples (biofield or mock) over the values of untreated control samples. Results: A trend of decreasing cell viability with increasing biofield dose was evident in the first set of experiments assessing dose–response; however, no such effect was evident in the second set of experiments evaluating biofield treatment distance. Mock experiments yielded relatively stable viability ratios in both sets of experiments. Linear regression analysis and hypothesis testing of the data taken as a whole did not yield statistical significance at p < 0.05. Conclusions: These results represent the first indication of a biofield treatment dose–response in a controlled laboratory setting. The data are inconclusive because of the inability of reproduce the cellular response in a replicate experiment.