The National Center for Complementary and Alternative Medicine was established by the Federal Government to define and monitor research developments regarding the various complementary and alternative medicine (CAM) therapies and products. 

CAM consists of various non-conventional/non-Western types of therapies or practices which can be offered with (complementary) or without (alternative) conventional medicine. CAM is a group of diverse medical and health care systems, practices, and products that are not generally considered part of conventional medicine. Complementary medicine is used together with conventional medicine, and alternative medicine is used in place of conventional medicine. Integrative medicine combines conventional and CAM treatments for which there is evidence of safety and effectiveness. 

While scientific evidence exists regarding some CAM therapies, for most there are key questions that are yet to be answered through well-designed scientific studies—questions such as whether these therapies are safe and whether they work for the purposes for which they are used. 

Some examples of CAM therapies include Reiki, yoga, and therapeutic touch. It defines Reiki as a type of CAM that utilizes an energy form of healing derived from an Eastern belief system.

The use of complementary and alternative medicine (CAM) is on the rise. According to the National Health Statistics Report “in 2007, almost four out of 10 adults (38.3%) had used some type of CAM therapy in the past 12 months”. 

O'Reilly in American Medical News indicated that at least one in five hospitals offer Reiki.  A study done in 2007 by the National Health Interview Survey indicates that 1.2 million adults and 161,000 children received one or more sessions of energy healing therapy such as Reiki in the previous year. According to the American Hospital Association, in 2007, 15% or over 800 American hospitals offered Reiki as part of hospital services