Based on the analysis of the essence and modern types of business models of enterprises, the basic professional service business model of the international consulting "Consultant" and reveals its main characteristics is substantiates: the B2B model, the modification of the "Producer" business model, the integration of elements of service and digital business models, customer orientation. Based on the Business Model Canvas, the main components of the basic business model of international consulting are revealed: key partners: partner intra-service and inter-service networks of the consulting firm; key activity: providing professional assistance to business organizations in solving problems of international economic activity; key resources: intellectual human, organizational, market; value proposition: the value services of international consulting for the client; relations with clients: client orientation, client-centricity, positive client experience, cooperation between consultants and clients at all stages of the consulting process; channels: omnichannel, cross-channel communications; customer segments: target audiences, customer networks; cost structure; income streams. Client networks as a component of the basic business model of international consulting are characterized and measures to optimize them are disclosed: forming a loyal attitude of clients to the consulting firm, consultants, and services; accumulation and protection of a network of regular customers; forming a positive customer experience; improving the efficiency of consultant-client relations; development of omnichannel provision of professional assistance to clients; ensuring client orientation of the personnel of the consulting firm; management of the value and quality of consulting services; introduction of new consulting services and technologies based on consulting innovations.