In this paper taxonomy has been developed to classify the different forms of ETO firms to enable a like-with-like comparison, arguing that existing taxonomies within the literature are inadequate for production planning and control research purposes. Successful production planning and control concepts from high volume, low variety producers cannot be directly applied, because of the unique nature of ETO products. Secondly through synthesis of the literature and the analysis of the three case studies we describe and examine the production planning and control activities characteristics of the ETO environment to distinguish the different environment within ETO production.