The present disclose provides a fluency aid comprising: a masking signal generator; a switch operable to switch the masking signal generator between an ON state and an OFF state, wherein, when in the ON state, the masking signal generator is operable to generate a masking signal; a sound generator operable to receive the masking signal from the masking signal generator and generate a masking sound for output to a user of the fluency aid; and a voice detector operable to detect a voice of the user, wherein the masking signal generator is operable to generate the masking signal at least until the voice of the user is detected by the voice detector.