Purpose - The purpose of the paper is to explore which are "the driving forces" of new ideas search in knowledge intensive business services (KIBS) companies having different knowledge bases. In particular, the study bases on the assumption that the level of structuring and formalization of the process of service development and ideas search can affect the level of innovativeness of the final product. Considering close and consistent relations of KIBS companies with their clients and customers another factor investigated in the paper is the degree of influence of the clients and market on the innovativeness of the product. Such connection was scarcely studied in previous literature since the researchers developed mostly theoretical models of innovation process in KIBS and service companies without testing them enough in practice. Furthermore, this study takes into account that different KIBS companies have different knowledge bases and that this can affect their business processes. Those bases are denoted as analytical, synthetic and symbolic where the terms clearly indicate their distinctive characteristics. Some studies pointed out that KIBS companies with different knowledge bases not only have different approaches to their innovation activities but also obtain different outcomes (Strambach, 2008, Pina and Tether, 2016). Design/methodology/approach - The case study method was adopted due to the exploratory nature of the research, novelty of the topic as well as the intention to analyse it at a practical level (Yin, 2003). Ten companies of different KIBS sectors were investigated which helped to analyse the NSD process in totally different environments characterized by different knowledge bases. The research was international and included companies from Italy, UK and Russia. Originality/value - The paper investigates the topic scarcely studied in the literature. Considering the selection of a sample of cases, the study allowed to investigate companies performing different activities and possessing different kinds of knowledge base. The research confirmed the propositions of previous researchers that companies with analytical and symbolic knowledge bases produce more innovative products. At the same time the research revealed that companies with "not pure knowledge base" (companies that combine two knowledge bases) create more innovative ideas if their PD/SD process is structured and codified. Practical implications - The research can help KIBS companies to understand how they can improve their Product/Service Development processes, and which models exist for the search and introduction of innovative ideas for new products/services.