The term polyglot speech synthesis refers to the process of producing speech in multiple languages and single speaker's voice from a single text-to-speech synthesis (TTS) system. This report reviews existing efforts in the literature to develop a polyglot TTS. Different methods described in this review mainly focus on developing a natural, intelligible, and cost-effective TTS system for multilingual text input. Since multilingual text is becoming very common in all applications of TTS, recent focus is made on developing a cost-effective polyglot TTS system, instead of conventional monolingual TTS. This review also discusses the pros and cons of different methods and mentions possible directions to overcome the limitations. © 2017 IETE.