The global nature of knowledge production has blurred the boundaries between many scientific and technical fields. New, enhanced processes, technologies, products, services, and business models emerge leveraging integrated solutions with different roots. The existing spillover or flow of knowledge has influenced the creation of new cross-disciplinary areas of research into this phenomenon: knowledge economics and management. This chapter explores the impact of knowledge spillover effects on companies' innovative activities and presents a classification of spillover effects based on seven attributes. The empirical analysis was conducted by using cross data of Russian industrial companies. The stratified sample comprises data for 252 high-tech industry enterprises. It is concluded that knowledge spillover effects contribute to changes in both business models of industrial enterprises and their performance. The degree of this influence directly depends on whether companies that have well-developed foreign relations possess a "critical mass" of absorption material. Knowledge spillover effects enable companies to ensure payback of investments in exports and innovations on a regular basis solely through the continuous inflow of complementary knowledge and experience from international partners. However, such openness comes along with loss of independence, the possibility of being taken over, and the need for the presence of a significant market demand.Keywords: the flow (spillover) of knowledge, knowledge spillover effects, research and development (R&D), channels and forms of innovation "cross-flow", knowledge transfer, export sales Current Issues in Knowledge Management 3 Knowledge Spillover Effects: Impact of Export Learning Effects on Companies' Innovative… DOI: http://dx.doi.org/10.5772/intechopen.86255