The bifurcated needle vaccination method used successfully against smallpox is a relatively simple technique that can be administered by personnel with only basic preparation and a minimum of training. This fact suggests that it could prove useful in campaigns of BCG vaccination against tuberculosis--especially for vaccination of newborns. With this end in mind, two studies were carried out in Santiago, Chile, to examine previously reported difficulties with the method and to assess its potential as an alternative to the best current method, that of intradermal inoculation. These studies indicated that previously reported variations in the results achieved by different vaccinators could be markedly reduced. However, they also found that the bifurcated needle method did not cause a sufficiently large dose of vaccine to enter the subject--even when fifteen needle strokes and a highly concentrated vaccine (160 mg per ml) were employed. It was thus concluded that although modification of the needle or other changes might ultimately yield satisfactory results, the bifurcated needle technique cannot yet be recommended for BCG vaccination of newborns.