Hi,

Good question. It depends what your ultimate final goal might be. If you simply wish to use oils effectively with bodywork, the Pacific Institute course would do -- also Google one from the Aromahead Institute ... IF you'd like to go on and be more precise about choosing and applying essential oils for specific "conditions", getting the RA would be the choice.

"Aroma" therapy (a mis-nomer, really, meaning "therapy with easily-evaporated molecules", not "those with aromas" ) is truly an entire branch of natural therapeutics. SO many oils, so many applications - which are very specific given one's condition(s). Just in the realm of bodywork, however (which is an art unto itself, I know) to be safe and work with the physiologic conditions typically encountered, a basic course will teach you everything you need - proper dilutions, a basic yet effective toolkit of oils, application and the like...

Hope this helps!
~ Eric