Contemporary third-party logistics (3PL) companies tend to broaden their competences in different fields and apart from traditional logistics services provide various value-added services to their customers. A systematic approach of 3PL resource management, as well as performance and quality indicator measurement are needed to forecast development of key performance indicators of a company. The purpose of this study is to discover contemporary tendencies of 3PL with regard to resources, performance and quality related issues, to determine resources, processes and quality indicators of 3PL, and to develop a system dynamics model for optimization of internal resources and processes of a company. The paper provides a systematic review of literature related to management of 3PL resources, quality and performance measurement. A model of management and optimization of 3PL resources and internal processes is developed by applying System Dynamics. The developed model consists of six blocks, namely, commercial activities, operations, procurement, administration, personnel management and quality management, representing different areas of internal activities of 3PL.