The themes are then restated in the tonic key and the piece ends. The form is defined by theorists such as Marx and Birnbach through harmonic motion, namely the modulation to the dominant in the exposition, the instability in the development and the tonic key in the recapitulation. The end result is a gradual build in tension to a climax, followed by a gradual release of tension.

             Variation movements consist of repeated binary forms with similar harmonic progressions. A theme is stated in the first binary area, which is altered in each new binary area. Typically the theme is ornamented or the intervalic relationships of the pitches in the theme are used in a new rhythmic idea (or the rhythm is used for a new set of pitches). A profusion of different variation techniques exist, which vary from composer to composer. Usually the underlying harmonic progression of the original binary area is preserved for each successive variation. The central idea of the form is to offer the audience amusing new variations on a theme, as even classicists did not strictly adhere to the 'standard" harmonic movements of the form. Dance movements strongly define one particular meter, and other formal principles often depend on the dance type imitated.

             The practice of free atonality and 12 – Tone method both require, by approximation or by methodical calculation, total chromaticism. Therefore, no harmonic progression, in the traditional sense, can exist. This creates problems in the abstract conception of sonata – allegro movements. In a form defined by tonal harmonic movement, how may atonality be used? This problem has led many composers of atonal music away from the symphonic genre. However, the form may also be viewed as a symmetrical build up and release of tension. Many composers of atonal music have used a broader conception of the sonata – allegro in their progressive symphonies.