Tempo giusto is a musical term that means “in exact time”, often directing a return to strict time following a period of rubato. or to play in “strict time” or “suitable time”.
General
The literal meaning of the term is 'in exact time'. Its most common meaning is to indicate a return to the main tempo after a temporary change. In the 17th and 18th centuries, tempo giusto referred to the idea that each meter has its own 'ideal' tempo. The larger the beat value of the meter, the slower the tempo. Therefore, meters with beat values of a minim/half note should be performed with a slow tempo; those with quaver/eighth note beats are fast; while those with crotchet/quarter note beats are performed at a moderate or middling tempo. The composer and music theoristJohann Kirnberger refined this idea by instructing the performer to consider the following details in combination when determining the best performance tempo of a piece: the tempo giusto of the meter, the tempo term, the particular rhythms in the piece, the 'character' of the piece, and the piece's genre. In this way, an experienced musician could rely on his/her intuition to find the 'right' tempo. Occasionally, a composer will mark a piece tempo giusto to request the performer to use his/her experience in this way: that is, to intuit the correct tempo from the structure and nature of the piece itself. From the mid-18th century, the notion of each meter having an 'ideal tempo' fell out of fashion, as composers started preferring to indicate tempo with tempo terms and with metronome markings.
Life Movement
Although tempo giusto is only sparsely sprinkled through musical time, it has recently reemerged. The term has given rise to a whole lifemovement, which advises the modern world to stop plowing through life at breakneck speed, and to start living instead at the “right tempo." Man is told to live in accordance with his own inner tempo. The artistic director of the Madison Symphony Orchestra, Maestro John DeMain, has said, “ow that I think about it, the idea of tempo giusto describes just about everything I do or aspire to."