This thesis addresses key aspects of practical visible light communication (VLC) systems. The research can be divided into three main topics. First, the limited data rate of current VLC systems is addressed in two ways. A performance analysis of the most important VLC modulation formats has been described and a new receiver for one of these schemes has been designed. Second, the interference that is usually caused by other LED luminaires that are not utilized for VLC, is discussed, and ways of mitigating its impact are described. Finally, an investigation of the communication characteristics of one of the most promising applications of VLC, visible light positioning, is described.