The Locrian mode starts on the seventh scale degree.  It is the least used mode, in fact you’ll find very few examples of its use.  In fact I can’t really remember ever using myself.

In the Key of C :  C D E F G A B C  the seventh scale degree is B so we have an B Locrian in this Key.

B Locrian:   B C D E F G A B    The intervals are therefore  S T T S T T T

If we compare to B Major : B  C# D# E F# G# A# B  we can see that the Locrian mode has a b2, b3, b5, b6 and b7 compared to the corresponding major scale.  The b5 is quite unusual; the locrian mode only really fits over diminished chords and doesn’t really have any chordal harmony.  It has a tense, unresolved sound.

An example pattern starting on the A string is shown below.  I’ve started on the A string to keep the fingering pattern fairly uniform.  As with all the modes, you definitely want to experiment a lot with playing this pattern in as many different positions as possible (audio here):


If you need a diagram showing the notes on the fretboard, one is available in the Ionian mode (Major scale) post.

I’ve included a very simple example over a Bdim chord to get you started (audio here).  By all means experiment, you never know you might find a sound you really like!