The use of complementary and alternative interventions is growing and gaining popularity, both in the UK and internationally, with significant financial and emotional implications. Complementary and alternative interventions are often utilised by parents of children with Autistic Spectrum Disorders and research has investigated parental beliefs. There is, however, limited understanding regarding what professionals believe about the use of alternative treatments. In this paper we explore the opinions of a range of different professionals about alternative treatments and found that while some have an open-minded opinion, there was a tendency to hold beliefs that these treatments are ineffective, that they give false hope and have potential to harm the child. We discuss the implications for this in terms of the importance of an open dialogue between professionals and families and consider the importance of this in relation to the popularity of these interventions.