Bhikkhu Bodhi is one of our favorite Theravāda buddhist writers. His work is always reliable, his knowledge and overview of the Pali Canon (the ancient Buddhist scriptures) admirable.
This work on the eightfold path, the path leading to liberation from suffering, is no exception. Bhikkhu Bodhi discusses each of the eight path factors extensively, with quotations from the Buddha, in his characteristic clear style.
The work is suitable for the novice practitioner, but absolutely worthwhile for anyone who has been practicing for some time as well.