Alasdair Roberts is a Scottish folk musician. He released a number of albums under the name Appendix Out, and following the 2001 album The Night is Advancing, under his own name.

Roberts was born in Swabia, Germany, to a German mother and Scottish father, though was raised in Kilmahog, a hamlet close to the small town of Callander, near Stirling in central Scotland. where he started playing the guitar and writing music. In 1994 he adopted the name 'Appendix Out' and started playing small venues. This is where he was discovered by American musician Will Oldham, and a contract with US label Drag City was soon to follow. Roberts is noted for both his own compositions and recitations of traditional songs, including on his album of traditional death ballads, No Earthly Man.