The Symphony No. 4 in G major by Gustav Mahler was composed from 1899 to 1900, though it incorporates a song originally written in 1892. That song, "Das himmlische Leben" ("The Heavenly Life"), presents a child's vision of heaven and is sung by a soprano in the symphony's Finale. Both smaller in orchestration and shorter in length than Mahler's earlier symphonies, the Fourth Symphony was initially planned to be in six movements, alternating between three instrumental and three vocal movements. The symphony's final form—begun in July 1899 at Bad Aussee and completed in August 1900 at Maiernigg—retains only one vocal movement (the Finale) and is in four movements: Bedächtig, nicht eilen (sonata form); In gemächlicher Bewegung, ohne Hast (scherzo and trio); Ruhevoll, poco adagio (double theme and variations); and Sehr behaglich (strophic variations). The premiere was performed in Munich on 25 November 1901 by the composer and the Kaim Orchestra, but it was met with negative audience and critical reception over the work's confusing intentions and perceived inferiority to the more well-received Second Symphony. The premiere was followed by a German tour, a 1901 Berlin premiere, and a 1902 Vienna premiere, which were met with near-unanimous condemnation of the symphony. Mahler conducted further performances of the symphony, sometimes to warm receptions, and the work received its American and British premieres in 1904 and 1905. The symphony's first edition was published in 1902, but Mahler made several more revisions up until 1911. After Mahler's death, the symphony continued to receive performances under conductors such as Willem Mengelberg and Bruno Walter, and its first recording is a 1930 Japanese rendition conducted by Hidemaro Konoye that is also the first electrical recording of any Mahler symphony. The musicologist Donald Mitchell believed the Fourth and its accessibility were largely responsible for the post-war rise in Mahler's popularity. The symphony uses cyclic form throughout its structure, such as in the anticipations of the Finale's main theme in the previous three movements. The first movement has been characterized as neoclassical in style, save for its complex development section. The second movement consists of scherzos depicting Death at his fiddle, which are contrasted with Ländler-like trios. The third movement's two themes are varied alternately before reaching a triple forte coda, and the Finale comprises verses from "Das himmlische Leben" sung in strophes that are separated by refrains of the first movement's opening. Certain themes and motifs in the Fourth Symphony are also found in Mahler's Second, Third, and Fifth Symphonies.

Das klagende Lied (Song of Lamentation) is a cantata by Gustav Mahler, composed between 1878 and 1880 and greatly revised over the next two decades. In its original form, Das klagende Lied is the earliest of his works to have survived.

Das Lied von der Erde (The song of the Earth) is an orchestral work for two voices and orchestra written by Gustav Mahler between 1908 and 1909. Described as a symphony when published, it comprises six movements for a large orchestra and two singers as the soloist alternating in the movements. Mahler specified that the two singers should be a tenor and an alto, or else a tenor and a baritone if an alto is not available. Mahler composed this work following the most painful period in his life, and the songs address themes such as those of living, parting and salvation. On the centenary of Mahler's birth, the composer and prominent Mahler conductor Leonard Bernstein described Das Lied von der Erde as Mahler's "greatest symphony". As with his later Symphony No. 9, Mahler did not live to hear Das Lied von der Erde performed.

Des Knaben Wunderhorn (The Boy’s Magic Horn) is a series of songs with music by Gustav Mahler, set either for voice and piano, or for voice and orchestra, based on texts of German folk poems chosen from a collection of the same name assembled by Achim von Arnim and Clemens Brentano and published by them, in heavily redacted form, between 1805 and 1808. Ten songs set for soprano or baritone and orchestra were first published by Mahler as a cycle in 1905, but in total 12 orchestral songs exist, and a similar number of songs for voice and piano.

The musical compositions of Gustav Mahler (1860–1911) are almost exclusively in the genres of song and symphony. In his juvenile years he attempted to write opera and instrumental works; all that survives musically from those times is a single movement from a piano quartet from around 1876–78. From 1880 onwards Mahler was a professional conductor whose composing activities had to be fitted around concert and theatrical engagements. Nevertheless, over the next 30 years he produced nine complete symphonies and sketches for a tenth, several orchestral song cycles and many other songs with piano or orchestral accompaniment. Mahler's symphonies are generally on an expansive scale, requiring large forces in performance, and are among the longest in the concert repertoire. Mahler scholar Deryck Cooke divides Mahler's compositions into separate creative phases, preceded by a "juvenile" period up to 1880. The earliest surviving whole work is Das klagende Lied (The Song of Lament), a cantata for soloists, chorus and orchestra which was completed in 1880 just before Mahler took up his first conducting post. In Cooke's chronology Mahler's first period as a mature composer extends over 20 years, to 1900, and includes his first four symphonies, his first song cycle Lieder eines fahrenden Gesellen ("Songs of a Wayfarer") and numerous other songs. The period includes Mahler's Wunderhorn phase, after his discovery in 1887 of the German folk-poems collected by Achim von Arnim and Clemens Brentano under the title Des Knaben Wunderhorn ("The Young Lad's Magic Horn"). Music critic Neville Cardus writes that this anthology nourished the composer's "pantheistic feelings about life and the world ... in which an all-embracing love [makes] all creatures kin." Mahler set 24 of these poems to music; three were absorbed into his Second, Third and Fourth symphonies; nine were used to create Volumes II and III of Lieder und Gesänge ("Songs and Airs"), and the remaining 12 were grouped to form Mahler's own Wunderhorn song cycle. Cooke dates Mahler's "middle period" as between 1901 and 1907, covering the trio of instrumental symphonies (Fifth, Sixth and Seventh), the massive Eighth Symphony, and the settings of poems by Friedrich Rückert including the Kindertotenlieder cycle and the Rückert-Lieder. The final period covers the last works: the symphonic Das Lied von der Erde ("The Song of the Earth") and the Ninth and Tenth Symphonies. None of these late works were performed during Mahler's lifetime. The unfinished Tenth Symphony was rendered by Deryck Cooke into a "performing version" which was first performed in London in 1964.

Kindertotenlieder (Songs on the Death of Children) is a song cycle (1904) for voice and orchestra by Gustav Mahler. The words of the songs are poems by Friedrich Rückert.

Lieder eines fahrenden Gesellen (Songs of a Wayfarer) is a song cycle by Gustav Mahler on his own texts. The cycle of four lieder for medium voice (often performed by women as well as men) was written around 1884–1885 in the wake of Mahler's unhappy love for soprano Johanna Richter, whom he met as the conductor of the opera house in Kassel, Germany, and orchestrated and revised in the 1890s.

Lieder und Gesänge is a collection of fourteen songs with piano accompaniment by Gustav Mahler. The title of the collection is sometimes given with the addendum aus der Jugendzeit (from the early days), but this addendum is not by Mahler. It is not even clear whether the subtitle refers to the songs being early works of Gustav Mahler (yet Mahler was aged 20 when he composed the earliest of the songs, not an adolescent), or whether the songs are meant to resemble memories of someone's younger days. The title might also simply refer to the source of the major part of the lyrics, Des Knaben Wunderhorn (The Youth's Magic Horn). The songs were composed from 1880 to 1889 and published in three booklets in 1892. Vol. 1 (composed 1880/81) Frühlingsmorgen - Spring morning (Richard Leander) Erinnerung - Memory (Richard Leander) Hans und Grete - Hans and Grethe (Gustav Mahler) Serenade aus Don Juan - Serenade (Tirso de Molina) Phantasie aus Don Juan - Imagination (Tirso de Molina) Vol. 2 (composed 1888/89; from: Des Knaben Wunderhorn) Um schlimme Kinder artig zu machen - How to make naughty children behave Ich ging mit Lust durch einen grünen Wald - I walked with joy Aus! Aus! - Out! Out! Starke Einbildungskraft - Strong Imagination Vol. 3 (composed 1888/89; from: Des Knaben Wunderhorn) Zu Straßburg auf der Schanz' - On the ramparts at Strasbourg Ablösung im Sommer - Changing of the summer relief Scheiden und Meiden - Parting is painful Nicht wiedersehen! - Never to meet again! Selbstgefühl - Self-esteem Together with the booklet "Sieben Lieder aus letzter Zeit" (Seven Songs of Latter Days), which consists of the five Rückert-Lieder and two of the Lieder aus "Des Knaben Wunderhorn", published in 1905, they now make up a collection known as 24 Songs by Mahler, published by International Music Company, New York, NY. Mahler's Ablösung im Sommer song was later extensively quoted in the 3rd movement of Mahler's 3rd Symphony. Orchestral versions of a selection of the songs were published by Luciano Berio in 1986 (Five Early Songs for Male Voice) and 1987 (Six Early Songs for Baritone and Orchestra). Orchestrations of five of the songs were also made by Colin Matthews and David Matthews in 1964. All 14 songs are now orchestrated and available for performance from Josef Weinberger Limited. The complete cycle was given its first performance by Regine Hangler (soprano) and the Warsaw Philharmonic under the baton of Jacek Kaspczyk at the Philharmonic Hall, Warsaw on 1 October 2016.

Lieder und Gesänge is a collection of fourteen songs with piano accompaniment by Gustav Mahler. The title of the collection is sometimes given with the addendum aus der Jugendzeit (from the early days), but this addendum is not by Mahler. It is not even clear whether the subtitle refers to the songs being early works of Gustav Mahler (yet Mahler was aged 20 when he composed the earliest of the songs, not an adolescent), or whether the songs are meant to resemble memories of someone's younger days. The title might also simply refer to the source of the major part of the lyrics, Des Knaben Wunderhorn (The Youth's Magic Horn). The songs were composed from 1880 to 1889 and published in three booklets in 1892. Vol. 1 (composed 1880/81) Frühlingsmorgen - Spring morning (Richard Leander) Erinnerung - Memory (Richard Leander) Hans und Grete - Hans and Grethe (Gustav Mahler) Serenade aus Don Juan - Serenade (Tirso de Molina) Phantasie aus Don Juan - Imagination (Tirso de Molina) Vol. 2 (composed 1888/89; from: Des Knaben Wunderhorn) Um schlimme Kinder artig zu machen - How to make naughty children behave Ich ging mit Lust durch einen grünen Wald - I walked with joy Aus! Aus! - Out! Out! Starke Einbildungskraft - Strong Imagination Vol. 3 (composed 1888/89; from: Des Knaben Wunderhorn) Zu Straßburg auf der Schanz' - On the ramparts at Strasbourg Ablösung im Sommer - Changing of the summer relief Scheiden und Meiden - Parting is painful Nicht wiedersehen! - Never to meet again! Selbstgefühl - Self-esteem Together with the booklet "Sieben Lieder aus letzter Zeit" (Seven Songs of Latter Days), which consists of the five Rückert-Lieder and two of the Lieder aus "Des Knaben Wunderhorn", published in 1905, they now make up a collection known as 24 Songs by Mahler, published by International Music Company, New York, NY. Mahler's Ablösung im Sommer song was later extensively quoted in the 3rd movement of Mahler's 3rd Symphony. Orchestral versions of a selection of the songs were published by Luciano Berio in 1986 (Five Early Songs for Male Voice) and 1987 (Six Early Songs for Baritone and Orchestra). Orchestrations of five of the songs were also made by Colin Matthews and David Matthews in 1964. All 14 songs are now orchestrated and available for performance from Josef Weinberger Limited. The complete cycle was given its first performance by Regine Hangler (soprano) and the Warsaw Philharmonic under the baton of Jacek Kaspczyk at the Philharmonic Hall, Warsaw on 1 October 2016.

Lieder und Gesänge is a collection of fourteen songs with piano accompaniment by Gustav Mahler. The title of the collection is sometimes given with the addendum aus der Jugendzeit (from the early days), but this addendum is not by Mahler. It is not even clear whether the subtitle refers to the songs being early works of Gustav Mahler (yet Mahler was aged 20 when he composed the earliest of the songs, not an adolescent), or whether the songs are meant to resemble memories of someone's younger days. The title might also simply refer to the source of the major part of the lyrics, Des Knaben Wunderhorn (The Youth's Magic Horn). The songs were composed from 1880 to 1889 and published in three booklets in 1892. Vol. 1 (composed 1880/81) Frühlingsmorgen - Spring morning (Richard Leander) Erinnerung - Memory (Richard Leander) Hans und Grete - Hans and Grethe (Gustav Mahler) Serenade aus Don Juan - Serenade (Tirso de Molina) Phantasie aus Don Juan - Imagination (Tirso de Molina) Vol. 2 (composed 1888/89; from: Des Knaben Wunderhorn) Um schlimme Kinder artig zu machen - How to make naughty children behave Ich ging mit Lust durch einen grünen Wald - I walked with joy Aus! Aus! - Out! Out! Starke Einbildungskraft - Strong Imagination Vol. 3 (composed 1888/89; from: Des Knaben Wunderhorn) Zu Straßburg auf der Schanz' - On the ramparts at Strasbourg Ablösung im Sommer - Changing of the summer relief Scheiden und Meiden - Parting is painful Nicht wiedersehen! - Never to meet again! Selbstgefühl - Self-esteem Together with the booklet "Sieben Lieder aus letzter Zeit" (Seven Songs of Latter Days), which consists of the five Rückert-Lieder and two of the Lieder aus "Des Knaben Wunderhorn", published in 1905, they now make up a collection known as 24 Songs by Mahler, published by International Music Company, New York, NY. Mahler's Ablösung im Sommer song was later extensively quoted in the 3rd movement of Mahler's 3rd Symphony. Orchestral versions of a selection of the songs were published by Luciano Berio in 1986 (Five Early Songs for Male Voice) and 1987 (Six Early Songs for Baritone and Orchestra). Orchestrations of five of the songs were also made by Colin Matthews and David Matthews in 1964. All 14 songs are now orchestrated and available for performance from Josef Weinberger Limited. The complete cycle was given its first performance by Regine Hangler (soprano) and the Warsaw Philharmonic under the baton of Jacek Kaspczyk at the Philharmonic Hall, Warsaw on 1 October 2016.

The Rückert-Lieder (Songs after Rückert) is a collection of five Lieder for voice and orchestra or piano by Gustav Mahler, setting poems by Friedrich Rückert to music. Four of the songs ("Blicke mir nicht in die Lieder!", "Ich atmet' einen linden Duft", "Ich bin der Welt abhanden gekommen", and "Um Mitternacht") were written in the summer of 1901 at Maiernigg, with one ("Liebst du um Schönheit") completed in the summer of 1902, also in Maiernigg. Both smaller in orchestration and briefer than Mahler's previous Des Knaben Wunderhorn settings, the collection marked a change of style from the childlike, often satirical Wunderhorn settings, to a more lyrical, contrapuntal style. The collection is often linked with the Kindertotenlieder, Mahler's other settings of Rückert's poetry, and with the 5th Symphony, and both were composed concurrently with the collection and contain subtle references to the Rückert-Lieder. The Rückert-Lieder (without "Liebst du um Schönheit") were premiered, alongside the Kindertotenlieder and several Wunderhorn settings, in Vienna on 29 January 1905 by Mahler and members of the Vienna Philharmonic, sung by Anton Moser (1872–1909) and Friedrich Weidemann. The songs met with a positive reception, though they were overshadowed by the Kindertotenlieder and the Wunderhorn settings which were performed, along with the Rückert-Lieder, in a repeat performance on 3 February 1905. The songs were first published as a collection in their versions for piano accompaniment in 1905, and later re-published, in full score, along with the Der Knaben Wunderhorn settings of "Revelge" and "Der Tamboursg’sell" in Sieben Lieder aus letzter Zeit (Seven Songs of Latter Days) in 1910. The Rückert-Lieder, along with the Kindertotenlieder and the 5th Symphony, are considered to be a turning point in Mahler's oeuvre, and many elements of these songs would anticipate later works such as Das Lied von der Erde.