The purpose of this paper is to refine existing theories on collaboration between users and suppliers in joint production equipment development projects by exploring critical collaboration activities throughout the lifecycle stages of the production equipment. By means of a literature review and a multiple case study of two equipment suppliers and two users, a lifecycle perspective on production equipment development is adopted. Our results show that collaboration intensity depends on the specific lifecycle stage of the production equipment. The contributions of this paper are illustrated in a developed lifecycle model in order to facilitate practitioners in organising critical collaboration activities.