Drilling technology of the Indus Valley Tradition was highly specialized and various types of chert and jasper were used to drill different types of materials. Earlier studies used primarily macroscopic observations to define features such as the manufacturing technique of drills, the raw materials and the mechanics of drilling. These generalizations can be revised given the discovery of important workshop areas and the availability of SEM, XRD and electrom microprobe analysis. This paper will summarize the current state of drilling research and define two categories of drills that were used in antiquity; taperd cylindrical drills and constricted cylindrical drills. Directions for future research on the relationship between drilling and other contemporaneous technologies are discussed.