Planetary Decades, also called Decennials, is a simple, clear, and useful Hellenistic timing technique. Though described by Hephaestio of Thebes, Vettius Valens, and Firmicus Maternus, it has yet to receive the attention it deserves. Partaking of the timing logic of Zodiac Releasing, and giving results similar to Firdaria and Vimshottari Dasha, it is simple to calculate, and is the perfect system for understanding when an aspect between planets will deliver on its full natal promise.