Wideband technology has got the potential to significantly improve the speech quality in telecommunication. However, it is required that all systems involved are carefully designed in order to achieve an optimum quality of the different conversational parameters. The paper describes the impairing factors which contribute to the speech quality as perceived by the user. The different parameters in the listening situation, the talking situation and in the conversational situation are introduced with respect to their special requirement in wideband. New subjective experiments and newly developed objective methods are introduced which help in the design of systems and algorithms in wideband.