Vibratory drilling refers to the process of drilling into rock by vibrating the drilling tool at audio‐frequencies. The basic mechanism of vibratory drilling was ascertained by preliminary laboratory experimentation to consist of a series of impacts on the rock at the frequency of vibration. A fundamental study of this basic mechanism, made by dropping weighted chisels on rock, showed that the primary parameter which determined the rate of penetration was the mechanical power input to the rock per unit cross section of hole; the values of the vibration frequency and of other variables were of minor consequence over wide ranges. A theoretical analysis was made of the vibration of an elongated magnetostriction transducer capable of generating the required power level, taking into account the distributed nature of the generation of vibrations. Intermediate power transducers have been built and tested and a high‐power transducer for down‐hole operation is under construction. [The material for this presentation is based on work carried out at the Battelle Memorial Institute under the sponsorship of Drilling Research, Inc., an organization formed by a group of major companies engaged in various phases of oil production for the purpose of investigating novel methods of rock drilling.]