II-V-I progression

Like I already said this progression is widely used in jazz. Open your Real Book there are plenty of II-V-I in it !
You'll often see his non-resolved version too : II-V



We already talked about the II-V-I in C Major in my previous thread about left hand rootless voicings : Dm7 - G7 - CM7

To understand what represents the chords of this progression you'll have to consider the major scale (e.g in C here) and put a degree (starting on I) on each note of this scale :

On each degree of the scale you can build a chord by stacking 3rds.
You all know the 3 notes chords which are 3 thirds stacked, but in jazz the chords are built with more notes to obtain a more colored sound.Let's take the first degree as an example :

You obtain here the CMaj7 chords








You can build like this many chords based on each degree of the scale. If you take a closer look to chords obtained here you'll see that each chord is not build with the same intervals (some are minor thirds, some are major thirds).
Here are the chords and their naming:

We will talk about each degree later on when talking about major scale harmonization. For the moment let's have a look on I, II and V degrees : CMaj7, Dm7 and G7

Those 3 chords are representing our II-V-I progression, in their primary position.








It is possible to extend those chords by stacking other thirds above those 4 notes, it gives a jazzy sound to the chords :

If you are playing in band with a bassist (his role is to play the root most of the time - I simplify of course), you can then remove the root from you voicing. See my 1st thread on left hand rootless voicings on II-V-I

We saw that those chords Dm7 - G7 - CMaj7 are entirely built with notes coming from C major scale. That's why you can play all notes of the major scale corresponding to the 1st degree of the progression when improvising on this progression. It's your alphabet for improvising on this progression.
In our example, it means you can play all those notes : C - D - E - F - G - A - B.

Work :

Search and work the II-V-I progresson in all tonalities, on the circle of fifths.
When you feel comfortable, play the chords with your left hand and try to improvise with the right hand on the corresponding major scale.

Now that you know a part of the improvisation alphabet, learn to use it by building words and sentences with it, and one day you'll be able to build a story.
If you have learn classical music when you were young, you already know this alphabet by practicing a lot of scales and arpeggios, you just need now to how to use it in a jazz context.

Have fun looking for II-V-I or II-V in the Real Book.

Enjoy and have fun !