All medical procedures, be they therapeutic or investigative, touch on the issue of consent – that is a measure of willingness on the part of the patient to undertake the procedure proposed. In this, ECT is no different to other therapeutic interventions. However, ECT has a particular status both within psychiatry and within the law that makes specific discussion of issues with regard to consent necessary.

General issues regarding consent

Electroconvulsive therapy is unusual in that consent obtained is for a course of treatments rather than for an individual procedure. It is also customary that the person seeking the consent will not be the person giving the treatment. The fact that the person receiving treatment has a psychiatric disorder sufficiently severe for ECT to be considered raises questions about their capacity; this makes it particularly important that consent is properly obtained and valid. It is unlawful and unethical to treat a patient who is capable of understanding the nature of any procedure, its purpose and implications, the anticipated benefits and any reasonably foreseeable adverse effects without first explaining it. The patient must then agree. Even if patients choose not to be informed of the full details of their diagnosis and treatment, they must be given the option of receiving this information. Guidance on good practice in consent can be found in publications from the Department of Health in England and Wales (2009), the Department of Health, Social Services and Public Safety in Northern Ireland (2003) and the Scottish Executive (2006), as well as from the General Medical Council (2008).

Obtaining valid consent should be considered a process rather than an event and it is necessary for patients to be given an adequate length of time to consider the benefits and drawbacks of the proposed treatment before making an informed decision. Patients should be informed of the risks and unwanted effects of ECT (Chapters 7–9) and they need to realise that a general anaesthetic is involved. If there are specific anaesthetic risks, the anaesthetist should explain these and obtain the necessary consent.

It is helpful for patients and carers to be provided with information obtained from different sources. Written information sheets may be useful (e.g. Appendix V); these need to be accompanied by the opportunity to discuss issues with members of the therapeutic team, family members, carers, advocates, etc.

THIS book is a team effort, driven by a shared desire to illuminate and celebrate the world's great classical traditions. Its ancestry as a piece of crosscultural musical analysis goes back a thousand years, to the ‘science of music’ of the medieval Arab theorists. Its European precursors include the sixteenthcentury Swiss theologian Jean de Léry, who notated antiphonal singing in Brazil, and the Moldavian polymath Prince Dimitrie Cantemir (1673–1723) who was enslaved by the Ottomans in Istanbul, became a de facto Turkish composer, and created the first notation for Turkish makam; also Captain James Cook, who made detailed descriptions of the music and dance of Pacific islanders in 1784. Meanwhile Chinese music was being admiringly analysed by French Jesuit missionaries – Chinese theorists had beaten their European counterparts in the race to solve the mathematics of equal temperament – and other Frenchmen were investigating the music of the Arab world. While serving on Napoleon Bonaparte's Egyptian campaign, Guillaume-André Villoteau made studies of Arab folk and art music, before going on to contrast those with the music of Greece and Armenia; his theories were then contested by the French composer Francesco Salvador-Daniel, who after a twelve-year musical sojourn in Algeria concluded, among other things, that Arab and Greek modes were one and the same. Long before ‘ethnomusicology’ was born in academe, the game was well established.

In recent years the ethnomusicologists’ findings have been magisterially presented in two great publications: in the ten massive volumes of the Garland Encyclopedia of World Music, and scattered through the twenty-nine volumes of the New Grove Dictionary of Music and Musicians. But our book is, we believe, the first panoptic survey of the world's classical musics (I explain in the Introduction why we have settled on that somewhat contentious adjective). Although much of its information may also be found in Grove and Garland – many of its writers were contributors to, or editors on, those projects – its tight focus permits presentation in a single volume, rather than scattered through a six-foot shelf of tomes.

As editor I am deeply indebted to my writers, who have patiently put their chapters through numerous drafts in pursuit of non-academic accessibility, while in no way traducing their (often very complicated) subject-matter. I must particularly thank Terry Miller, whose resourceful problem-solving assistance has extended far beyond his own signed contributions; also his colleague Andrew Shahriari, for additional information on Persian classical music.