William Walton in the context of "Crown Imperial (march)"

Orchestration is the study or practice of writing music for an orchestra (or, more loosely, for any musical ensemble, such as a concert band) or of adapting music composed for another medium for an orchestra. Also called "instrumentation", orchestration is the assignment of different instruments to play the different parts (e.g., melody, bassline, etc.) of a musical work. For example, a work for solo piano could be adapted and orchestrated so that an orchestra could perform the piece, or a concert band piece could be orchestrated for a symphony orchestra.

In classical music, composers have historically orchestrated their own music. Only gradually over the course of music history did orchestration come to be regarded as a separate compositional art and profession in itself. In modern classical music, composers almost invariably orchestrate their own work. Two notable exceptions to this are Ravel's orchestration of Mussorgsky's solo piano work Pictures at an Exhibition and Malcolm Arnold's orchestration of William Walton's String Quartet in A minor, producing the latter's Sonata for Strings.

Chamber opera is a designation for operas written to be performed with a chamber ensemble rather than a full orchestra. Early 20th-century operas of this type include Paul Hindemith's Cardillac (1926). Earlier small-scale operas such as Pergolesi's La serva padrona (1733) are sometimes known as chamber operas.

Other 20th-century examples include Gustav Holst's Savitri (1916). Benjamin Britten wrote works in this category in the 1940s when the English Opera Group needed works that could easily be taken on tour and performed in a variety of small performance spaces. The Rape of Lucretia (1946) was his first example in the genre, and Britten followed it with Albert Herring (1947), The Turn of the Screw (1954) and Curlew River (1964). Other composers, including Hans Werner Henze, Harrison Birtwistle, Thomas Adès, George Benjamin, William Walton, and Philip Glass have written in this genre.

Façade is a series of poems by Edith Sitwell, best known as part of Façade – An Entertainment in which the poems are recited over an instrumental accompaniment by William Walton. The poems and the music exist in several versions.

Sitwell began to publish some of the Façade poems in 1918, in the literary magazine Wheels. In 1922 many of them were given an orchestral accompaniment by Walton, Sitwell's protégé. The "entertainment" was first performed in public on 12 June 1923 at the Aeolian Hall in London, and achieved both fame and notoriety for its unconventional form. Walton arranged two suites of his music for full orchestra. When Frederick Ashton made a ballet of Façade in 1931, Sitwell did not wish her poems to be part of it, and the orchestral arrangements were used.

Belshazzar's Feast is a cantata by the English composer William Walton. It was first performed at the Leeds Festival on 8 October 1931, with the baritone Dennis Noble, the London Symphony Orchestra and the Leeds Festival Chorus, conducted by Malcolm Sargent. The work has remained one of Walton's most celebrated compositions. Osbert Sitwell selected the text from the Bible, primarily the Book of Daniel and Psalm 137. The work is dedicated to Walton's friend and benefactor Lord Berners.

The Viola Concerto by William Walton was written in 1929 and first performed at the Queen's Hall, London on 3 October of that year by Paul Hindemith as soloist and the composer conducting. It had been written with the violist Lionel Tertis in mind, and he took the work up after initially rejecting it. The concerto established Walton as a substantial figure in British music and has been recorded by leading violists internationally. Walton revised the instrumentation of the concerto in 1961, lightening the orchestral textures.

The Symphony No. 1 in B♭ minor is one of two symphonies by the English composer William Walton. The composer had difficulty in completing the work, and its first public performance was given without the finale, in 1934. The complete four-movement work was premiered the following year.

The work shows the influence of Sibelius, particularly in its musical structure. It is among the best-known symphonies by British composers, and has received numerous recordings from within a month of the 1935 premiere to the 21st century.

Orb and Sceptre is a march for orchestra written by William Walton for the coronation of Queen Elizabeth II in Westminster Abbey, London, on 2 June 1953. It follows the pattern of earlier concert marches by Elgar and Walton himself in consisting of a brisk opening section followed by a broad melody in the middle, trio, section and a return to the lively first theme to conclude the piece after a second appearance of the big tune.

The Sitwells (Edith Sitwell, Osbert Sitwell, Sacheverell Sitwell), from Scarborough, North Yorkshire and the family seat of Renishaw Hall, were three siblings who formed an identifiable literary and artistic clique around themselves in London in the period roughly 1916 to 1930. This was marked by some well-publicised events, notably Edith's Façade with music by William Walton, with its public debut in 1923. All three Sitwells wrote; for a while their circle was considered by some to rival Bloomsbury, though others dismissed them as attention-seekers rather than serious artists.