Alaryngeal speech enhancement and restoration systems are proposed to improve the intelligibility and quality of speech signal produced by either an electronic larynx or by using esophageal methods. The enhancement system reduces the background noise produced by the electronic larynx, while the restoration systems identify the voiced segments of alaryngeal speech signal, by using pattern recognition methods, and replaces these by their equivalent voiced segments of normal speech. Evaluation results show that proposed systems provides a fairly good improvement of the quality and intelligibility of ALT generated speech.