Embedded Files
Secondary Dominants
Secondary Dominants
You already know that the V7 chord creates the strongest pull in tonal music — it is the engine of every II-V-I. Now here is a powerful idea: any chord in a key can be temporarily treated as a tonic, and preceded by its own V7. That V7 — borrowed to pull toward a chord other than the I — is called a secondary dominant.
Secondary dominants appear in virtually every jazz standard. They are the reason some chord progressions feel like they have extra momentum — a surge of tension before landing on an unexpected but satisfying chord. Once you can recognize and build them, you will hear them everywhere.
💡 This lesson builds on Chord Function & Degrees and Common Jazz Progressions. Make sure you understand the II-V-I and the turnaround before continuing.
The Core Idea
The Core Idea
In C major, the only "natural" Dominant 7 chord is G7 — the V7 that resolves to Cmaj7. Every other degree produces a Major 7, Minor 7, or Half-Diminished chord. But jazz musicians discovered that you can temporarily install a Dominant 7 chord in front of any diatonic chord, as if that chord were momentarily a new tonic. The installed Dominant 7 is the secondary dominant — written as "V7 of [target chord]" or "V7/x."
Example — V7/II (the most common secondary dominant):
In C major, the IIm7 chord is Dm7. Its own V7 chord would be A7 (a fifth above D). So placing A7 before Dm7 briefly treats D as a temporary tonic — and the resolution A7 → Dm7 has the same V7 → I pull as G7 → Cmaj7, just in a different tonal center.
A7 → Dm7 = V7/ii → ii
You already heard this in the turnaround lesson: Cmaj7 - A7 - Dm7 - G7. That A7 is a secondary dominant — it creates a surge of energy before Dm7 that Am7 (the diatonic chord) simply cannot produce.
How to Build Any Secondary Dominant
How to Build Any Secondary Dominant
The rule is simple: go up a perfect fifth from the target chord's root and build a Dominant 7 chord. That Dominant 7 is the secondary dominant of your target.
Formula: Target chord root + perfect 5th up = secondary dominant root
V7/ii: target = Dm7 (root D), fifth above D = A → A7
V7/iii: target = Em7 (root E), fifth above E = B → B7
V7/IV: target = Fmaj7 (root F), fifth above F = C → C7
V7/V: target = G7 (root G), fifth above G = D → D7
V7/vi: target = Am7 (root A), fifth above A = E → E7
The Secondary Dominants of C Major
The Secondary Dominants of C Major
How to Recognize Them in a Lead Sheet
How to Recognize Them in a Lead Sheet
A secondary dominant always stands out because it contains a note that does not belong to the key. In C major, any Dominant 7 chord other than G7 is a secondary dominant. The tell-tale sign is a natural or raised note that seems "wrong" for the key — a C# in A7, a D# in B7, a Bb in C7. These accidentals are the fingerprint of a secondary dominant.
The shortcut: when you see a Dominant 7 chord that is not the diatonic V7 of the key, ask "which chord does this resolve to?" The answer is always a fifth below the secondary dominant's root. A7 resolves to D. D7 resolves to G. E7 resolves to A. Once you know this reflex, any secondary dominant becomes instantly readable.
🎹 Play It — Adding a Secondary Dominant
Compare the same progression with and without a secondary dominant:
Cmaj7 - Am7 - Dm7 - G7 (diatonic — smooth)
Cmaj7 - A7 - Dm7 - G7 (with V7/ii — more drive)
That single change — Am7 to A7 — adds a C# that creates a strong pull toward Dm7. The progression suddenly has more forward momentum. That is what a secondary dominant does: it injects V7 energy into a chord that would otherwise just pass through.
Chains of Dominants
Chains of Dominants
Secondary dominants can be chained together — each one resolving to the next, which itself becomes a secondary dominant for the following chord. This creates a powerful harmonic chain that moves counter-clockwise around the Circle of Fifths, building tension with each step before finally arriving at the tonic.
E7 — A7 — D7 — G7 — Cmaj7
V7/vi - V7/ii - V7/V - V7 - I : each chord is a secondary dominant of the next
This kind of chain appears frequently in bridges and long phrases. Each Dominant 7 temporarily tonicizes the next chord, creating a sequence of local V7 → I resolutions that carry the music through several tonal centers before landing on the home key.
You can hear this in the bridge of many standards — a series of Dominant 7 chords descending by fifths (E7 → A7 → D7 → G7) that releases all its accumulated tension on the final Imaj7. The longer the chain, the more satisfying the eventual resolution.
🎹 Play It — The Chain of Dominants
Play this chain slowly, listening to how each chord pulls urgently toward the next:
E7 - A7 - D7 - G7 - Cmaj7
Now compare with the diatonic version:
Em7 - Am7 - Dm7 - G7 - Cmaj7
The chain of dominant 7 chords creates a relentless forward pull that the diatonic version simply cannot match. Every chord in the chain contains a leading tone pointing to the next root — the tension accumulates with each step and the resolution on Cmaj7 feels earned.
Secondary Dominants in Standards
Secondary Dominants in Standards
Secondary dominants are everywhere once you know what to look for. In Fly Me to the Moon, the progression moves through several secondary dominants that tonicize different degrees before arriving at the tonic. In All of Me, the E7 in bar 5 is a V7/vi that temporarily pulls toward Am — a deceptive-sounding move that gives the tune its characteristic harmonic color.
The key insight is this: secondary dominants do not change the key. They momentarily borrow V7 energy from another tonal center, use it to propel the music forward, and then release it back into the main key. The key signature never changes — only the tension level does.
Quick Summary
Quick Summary
Key takeaways:
A secondary dominant is a Dominant 7 chord that temporarily tonicizes a non-tonic chord — written as V7/x
To build one: go up a perfect fifth from the target chord's root and build a Dominant 7
In C major: A7 (V7/ii), B7 (V7/iii), C7 (V7/IV), D7 (V7/V), E7 (V7/vi)
Recognition shortcut: any Dominant 7 that is not the diatonic V7 resolves a fifth down to its target
Secondary dominants can be chained (E7-A7-D7-G7-C) for cumulative tension
They do not change the key — they temporarily borrow V7 energy and release it back into the main progression
What's Next
What's Next
You now have the complete harmonic foundation of jazz — from chord construction to the progressions that power every standard. The next step is applying all of this to real music, note by note, standard by standard:
Google Sites
Report abuse