Thanks my friend Randy in DE who shared this link from the Early Show on CBS with me. When you attend a Yoga class, you need to make sure the Yoga teacher is properly certified. A good Yoga teacher is also expanding his/her knowledge continuously and bring the new information back to the class. The most important thing is: regardless who the teacher is and how experience you are, always practice with full awareness. Not only it will prevent injury, but also enable you to gain the true benefits from practicing Yoga.