Annie Besant unfolds in this book the spiritual message of the Bhagavadgita, after having studied it deeply, translated it into English and , more than anythying, also practised yoga. She pointed out:
'The Bhagavadgita, in its very essence is that which it is called at the end of each of the adhyayas (chapters) - a Yoga-Sastra. Unless we can learn yoga from this volume, it will, for us, have failed in its purpose.'
Guidance can be found here for learning yoga in its many aspects.