The main aim of this chapter was to discuss speech recognition and synthesis and how we can implement it on our robot. By adding speech functionalities in our robot, we can make the robot more interactive than before. We saw what are the processes involved in the speech recognition and synthesis process. We also saw the block diagram of these processes and the functions of each block. After discussing the blocks, we saw some interesting speech recognition frameworks (such as Sphinx/Pocket Sphinx, Julius, and Windows Speech SDK and synthesis libraries such as eSpeak and Festival). After discussing these libraries, we discussed and worked with the Python interfacing of each library. Towards the end of this chapter, we discussed and worked with the ROS packages that perform speech recognition and synthesis functionalities.