[The pterional craniotomy: step by step].

This article intends to describe in a didactical and practical manner the frontotemporosphenoidal craniotomy, that is usually known as pterional craniotomy and that constitute the cranial approach mostly utilized in the modern neurosurgery. This is then basically a descriptive text, divided according to the main stages involved in this procedure, and that describes with details how the authors currently perform this craniotomy.