This chapter endeavours to lead the scientific discussion regarding which IPSE factors are expected to, in theory, lower the environmental impact of a life cycle compared to a traditional product sales business. To do so, the IPSE concept is introduced, first with an emphasis on engineering processes rather than an object such as PSS. In the following sections, four aspects from theory will be discussed: product development, information asymmetry, economies of scale, and risk. These sections discuss how environmental impacts are influenced from a product life cycle perspective, and highlight crucial factors theoretically. They are followed by an overall discussion and an examination of some promising future work. The chapter provides the research community with a first theoretical cornerstone regarding environmental performance by IPSE. To practitioners, it will be an eye opener for how they engineer