All of our Essential Oils are 100% pure essential oils. These would be considered "therapeutic grade" if there was such a grading system. Basically pure oils are therapeutic grade opposed to synthetic blends. You can usually tell a pure oil by the dark bottles (clear bottles can sometimes indicate a synthetic oil as it does not need to be protected from light). Some oils that are more rare or expensive can be in a dilution of jojoba or other seed/carrier oils. That does not diminish it's properties, but simply makes it more affordable and can usually be used "neat" (can be applied directly to the skin) since it is diluted. ALL essential oils should be diluted in a carrier oil before applying topically as they can cause burns or other reactions.
I have researched the companies with which I deal and feel confident that their products are pure and that they strive to maintain a high quality oil.