ABSTRACT: There is a long tradition of writing that considers how individuals with an intellectual disability respond to, and are affected by music. This paper, which examines descriptive and philosophical literature, discusses surveys that consider client responses, methodological issues, and music therapy provision; reports that provide general accounts of work settings and music therapy programmes; and case studies that illustrate the potential benefits of improvisation, Music Activity Therapy, and receptive music interventions. Finally, this paper identifies philosophical writing that is underpinned by the desire to promote music as a viable and credible treatment option for individuals with an intellectual disability. This paper not only considers clinical practice by directing readers towards examples from the extant literature that identify outcomes, but it also reflects on the relative strengths, and weaknesses, of the different methods of enquiry. In 1959, Juliette Alvin, widely considered the mother of mu- sic therapy in Great Britain, outlined how 24 children (6 to 16 years) with mild to severe intellectual disability responded to six short concerts that also included contact with the per- former (the author), and her instrument (a cello). She de- scribed their vocal and physical reactions ("some made noises as if trying to sing or whistled softly; others moved their hands or feet, beat time with their fingers" (Alvin, 1959, page 991)); identified changes in their level of engagement ("immediate curiosity became interest, and their desire to participate was more than mere imitation" (page 991)); and noted how the children's "self control and confidence developed" as they "came forward to play a note on the cello" (page 992). Juliette Alvin was not the first music therapist to indicate how music therapy met the needs, and developed the potential, of individuals with an intellectual disability, and she was not to be the last. This paper, and a subsequent one, will provide a detailed appraisal of that writing: something hitherto absent from the music therapy literature. Intellectual disability is the term used by the World Health Organisation (WHO), and adopted in Australasia, that equates with developmental disability and mental retardation in North America, and learning disability in the UK (McConkey, 2003). The person with an intellectual disability is limited intellectually. The difficulty they experience understanding, learning, and remembering new things, and generalising any learning to new situations, affects their communication, self-care, home living, self-direction, functional academic, and social/interpersonal skills. Furthermore, it may limit access to community services, and have an impact on work, leisure, health, and safety (American Psychiatric Association, 2000). This review is organised according to the method of enquiry. The literature is arranged into three of the four broad categories put forward by Jellison (1973), and subsequently employed by Bunt (1984), and Hooper, Lindsay, and Richardson (1991) when they discussed music therapy research in Great Britain. The three categories are: (1) descriptive (surveys, reports, case studies, literature reviews/meta-analyses). (2) philosophical (speculation, criticism, indicators for research). (3) experimental (i.e. either controlled research carried out within or between subjects, comparing interventions, or recording pre- and post- intervention responses). (Jellison's fourth method of enquiry is historical writing. It is not included as a separate category in this review, although reference is made to an historical account when the reports are discussed). This paper deals with the descriptive and philosophical writing. A second paper focuses on the experimental category. In each case, the aim is not only to highlight examples from clinical practice that identify outcomes, but also, by organising the review by method of enquiry, to allow some reflection on the strengths, and weaknesses, of the music therapy research in this area of clinical practice. …