Schubert's 'Abschied von einem Freunde' (Farewell to a Friend) is a beautifully crafted piece that captures a bittersweet mix of affection and parting. It features lyrical melodies and a flowing, pianistic texture.
The piece requires careful attention to dynamic contrast and the ability to project the melody over a rich accompaniment.
Abschied von einem Freunde (D.578) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Abschied von einem Freunde (D.578) lasts about 7 minutes.
Abschied von einem Freunde (D.578) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.