The “Agnes Fast” craniotomy is a fast and simple way of performing the pterional craniotomy while preserving the temporalis muscle, together with its fascia and bony attachment. Using this technique, the surgeon need not divide the temporalis muscle, separate it from its bony attachment, or perform an interfacial dissection. With a little practice, this craniotomy can be performed in less than 5 minutes and is highly recommended in emergent settings.