From the Primary Series to four Advanced stages: how the six-series system is structured, who advances when - and why backbends become central.
What actually comes after the Primary Series - and who decides when you're ready for it? Ashtanga consists of a total of six series: the Primary Series, the Intermediate Series, and four Advanced series (A through D). Each builds on the previous one, with its own physical and energetic focus.
The Primary Series ("Yoga Chikitsa", "yoga therapy") mainly cleanses and detoxifies the body. The Intermediate Series ("Nadi Shodhana", "purification of the energy channels") brings more intense backbends, deeper hip openers and first headstand variations - a noticeably different focus that works more on the nervous system than on pure strength or flexibility. The four Advanced series, finally, are meant for very experienced practitioners and demand extreme strength, extreme flexibility and complete control of body and mind.
The key difference from many other progression systems: traditionally, the teacher decides when a new pose or series is "given" - not ambition, not calendar time, not comparison with others. This gatekeeping logic feels foreign to many Western practitioners at first, but it specifically guards against overreach in a system that already leans toward overuse (see the injury guide in this series).
Important for context: most Ashtanga practitioners spend years or decades practicing exclusively the Primary Series and part of the Intermediate Series - and that isn't an incomplete practice, it's the actual, fulfilling core of the method for the vast majority.
Before even thinking about the next series, the Primary Series must sit securely, physically and with stable breath. That's not an administrative step, it's the actual prerequisite - the following series build directly on this base.
The Intermediate Series adds backbends, deep hip openers and first headstand variations, and is traditionally described as purifying the energy channels. In practice that means more focus on spinal flexibility and nervous-system regulation than on pure muscular strength.
The move to the Intermediate Series pushes backbends like urdhva dhanurasana (wheel) much more into the center. Build the mobility for it consistently from the ground up: floor exercises with bent legs first, then wall-assisted variations, and only last the free stand.
A common mistake in backbends: searching for the movement in the lower back alone. Instead, consciously engage the abdomen, push the hips forward and draw the ribs in lightly - that spreads the curve more evenly across the whole spine instead of concentrating it at one point.
The Advanced series A through D are a realistic goal for very few practitioners and require years of consistent practice. Knowing about them helps you understand the whole system, without them being a necessary milestone.
Backbends are among the movements with the highest injury potential in the whole system when practiced too early or with the wrong focus. Searching for the curve purely in the lower back instead of spreading it across the spine risks compression in the sacroiliac joint and lower lumbar spine - often with long-term consequences.
Build the path to the Intermediate Series consistently through wall variations and floor exercises rather than attempting the free stand too soon. With existing back issues, guidance from an experienced teacher is especially important here.
Measure your backbend progress not by the depth of the curve, but by how evenly it's distributed across the spine. A moderate, even curve is safer and more sustainable long-term than an extreme curve concentrated mainly in the lower back.
Six: the Primary Series, the Intermediate Series, and four Advanced series (A through D). Each series builds physically and energetically on the previous one.
Traditionally the teacher, not the practitioner themselves. This gatekeeping logic is meant to guard against overreach and the overuse injuries that can follow from it.
The Primary Series focuses on physical cleansing and base strength; the Intermediate Series brings significantly more backbends and deep hip openers and works more on the nervous system than on pure muscular strength.
No. The four Advanced series are a realistic goal for very few and aren't a necessary part of a fulfilling Ashtanga practice. Many practitioners stay permanently with Primary or Intermediate.
Ashtanga Yoga: The Fixed Series Explained Simply