Chord Functions
Once you start using secondary chords, it becomes obvious that there is always more than one chord which can be used to harmonize any note of a melody. Although it is possible to progress form any chord to any other chord, certain progressions sound better than others and have therefore become part of traditional harmony. Common functions for each chord in a major key are shown here.
I Harmonizes degrees 1, 3 or 5. Usually ends a progression. Can begin a progression.
II Harmonizes degrees 2, 4 or 6. Can substitute for chord IV. Usually leads to chord V.
III Harmonizes degrees 3, 5 or 7. Can substitute for I or V. Usually leads to VI or IV.
IV Harmonizes degrees 4, 6 or 1. Can substitute for I, II or VI. Usually leads to V or I.
V Harmonizes degrees 5, 7 or 2. Can substitute for VII. Usually leads to I or VI.
VI Harmonizes Degrees 6, 1 or 3. Can substitute for I or IV. Usually leads to II or IV.
VII Harmonizes Degrees 7, 2 or 4. Can substitute for V or II. Usually leads to III or I.
