The main goal of this paper is to present an analysis of the impact of relational competencies (communication, cooperation, integration) on supply chain management practices and on its performance. The paper presents a conceptual model that was conceived, used and tested to study the impact of relational competencies on the company's business performance. The basis for the research was the supply chain of an electric car manufacturer in the immediate vicinity of Slovenia. To demonstrate the effect of relational competencies on supply chain management, organizational approach and business performance of the studied company, the method of functional analysis, correlation analysis method and modeling of structural equations were used. Data were collected from 89 supplier companies from Slovenia, Croatia, Austria, Germany and Switzerland, which are suppliers to the studied company, which represents a response rate of 52.1%.