The aim of the research described in this thesis is to evaluate the relationship between the service capabilities and performance of UK and Taiwanese third-party logistics (3PL) providers. A study is presented based on a survey conducted in 2007. The study explores the interrelationships between 3PL service capabilities, operational performance and financial performance. The results identify the most important services offered by 3PLs and the most important aspects of 3PL operational performance. The operational performance offered by 3PLs is found to have a positive relationship with their financial performance. The positive relationship between key aspects of operational performance and financial performance are also confirmed in this study. The range of service provision offered by 3PLs cannot directly influence 3PLs' financial performance. Although it appears that 3PL providers with a broader range of service provision have generally better financial performance both in Taiwan and the UK, but through a better operational performance, 3PLs will gain superior financial performance. The direct relationship and the context dependent relationship of service capabilities and operational performance offered by 3PLs on their financial performance are discussed in this research. The results also suggest that excellence in operations is more important than wide-ranging service provision. For some developing 3PLs, aligning high levels of operational performance with customers' key priorities is a necessary strategy. In addition, the paper provides a comprehensive review of the dimensions of 3PL operational performance and the range of 3PL services offered.