Considering various forms of in vitro plant tissue cultures, cell suspension culture is most amenable to large-scale production of natural compounds, owing primarily to its superior culture homogeneity. This fact has already been demonstrated in several large-scale applications, including the commercial shikonin process. The scope of this work is to review the state of the art in bioprocessing technologies pertinent to the secondary metabolite production from suspension cultures of callus cells. In the first part of the review, plant cell physiology relevant to bioprocess design is considered. This is followed by an in-depth discussion on the bioreactor design and operation and its effect on plant cell suspension cultures. Finally, recent commercial exploitation and development are summarized. Following the review, related patents and literature are listed.