Knowledge of properties of the human voice source is fundamental to speech synthesis and speech recognition, but also for the understanding of voice disorders and their early detection. There are several ways to investigate voice source properties out of which acoustic analysis is of interest because it is not invasive while it can convey many details of vocal behaviour. Voice source properties are highly complex and multidimensional in the sense that fundamental frequency, vocal intensity, spectral properties are involved, including their time varying characteristics. For a proper understanding of vocal behaviour, all these variables should be studied jointly. An acoustic voice profile measurement (or phonetogram) is a very useful step into that direction. Voice profile measurement has seen an enormous development over the last 40 years in which Utrecht University has played a significant role. This development will be described, as well as the current status, while a series of future extensions will be outlined. The latter will focus on issues of time track analysis (how previous phonations influence current ones), vocal registers, and the comparison of voice profiles (for which HMM techniques can be used). A laptop voice profile measurement system will be available for demonstrations.