Groupings of two or more staves form staff systems. A system is a group of staves read simultaneously; systems are grouped by combinations of braces, brackets, and the left-end bar. A single vertical line (the left end bar line) is used to vertically connect all staves within a single system.

The Grand Staff is a combination of two staves joined by a brace, which should be slightly separated from the left bar line and centered between the staves it connects. The top and bottom staves commonly use treble and bass clefs, respectively. The grand staff is most often used with keyboard instruments and with reduced scores. It can be considered an eleven-line staff with middle C occupying an invisible eleventh line between the treble and bass staves.