In this paper the decision situation of an automobile manufacturer (OEM), which alternative powertrains to promote, is presented by discussing the three planning levels technology, product and product portfolio planning, the interdependencies between the levels as well as the necessity to integrate a life-cycle perspective. Based on this, a concept for the life-cycle-oriented symbiosis of technology, product and product portfolio planning is developed. The concept consists of three planning modules each incorporating a life-cycle perspective: technology planning, product planning and product portfolio planning. Within each module, technologies, products and the resulting portfolio are analyzed, evaluated and selected according to the company objective(s). Referring to the developed concept, existing approaches to support the implementation and open challenges are discussed.