"Bb Major" (or the key of Bb) is a major scale based on Bb, with the pitches Bb C D Eb F G A. Its key signature has two flats: Bb Eb. Its Relative Minor scale is G Minor. Its Parallel Minor is Bb Minor. B-flat major is a suitable key for most wind instruments, especially those for which it is their home key, such as clarinets, trumpets, tenor saxophone, soprano saxophone and flutes in B-flat.

The primary chords for any major key are the I, IV and V chords of its corresponding major scale. For Bb Major, the primary chords are: Bb, Eb, F and F7. From the primary and secondary chords of a major key, countless songs and chords progressions can be played.

The secondary chords for any major key are the II, III and VI chords of it's corresponding major scale. For Bb Major the secondary chords are: Cm, Dm and Gm, From the primary and secondary chords of a major key countless songs and chords progressions can be played.

Common chord progressions for the key of Bb. Using the primary and seconday chords for the key explore these common chord progressions for the key of Bb.

Harmonic Analysis is the understanding of the functional sequence of chords. It is the process used to analyze the harmonic structure of a progression, song or composition. This analysis is then used to make scale selections for improvisation and chord substitution.