Abstract: The present invention relates to a method and apparatus for speech intelligibility enhancement. First, the noise estimator determines the amount of ambient noise when the listener is placed in a high ambient noise environment. Second, the perceptual feature associated with speech intelligibility is enhanced with minimal processing artifacts. Third, the listener's volume gain is automatically and adaptively adjusted based on the psycho-acoustic model. The method and apparatus has ample capability to enhance speech intelligibility in any noisy environment conditions, and hence it can be a more desired solution than manual volume adjustment. Thus, the present invention can be implemented in mobile handsets, telephones, public address systems, and the like.