Purpose: The thesis has two objectives. First, from a theoretical perspective, it investigates the interrelationship between the theory of supply chain flexibility, the notion of leagility and the concept of 4PL. The second and primary objective is to explore the influence 4PLs have on leagile supply chain structures by integrating different types of both vendor and sourcing flexibility to analyse further whether 4PL providers facilitate a novel form of leagility. Design, Methodology & Approach: To suit the exploratory nature of the investigation, the thesis adopts an interpretivist, qualitative approach to research. Three semi-structured interviews were conducted with a sample of purposively selected 4PL providers. Furthermore, the study follows an abductive research approach because the underlying objective is not to test but rather to propose new theory in the field of supply chain management. The empirical findings are analysed based on a template analysis, while the quality of the research design is assessed by the criteria of credibility, transferability, dependability and conformability. Findings: From a theoretical perspective, a 4PL Leagility Framework is proposed that defines nine different types of leagility. These are generally interrelated; consequently, three particular categories were identified that determine the overall leagile configuration of a supply network: the family of sourcing leagility, vendor leagility or supplier leagility. Empirically, however, the framework could not have been tested to its full extent, meaning that none of the nine forms of leagility is validated. The study further concludes that 4PL providers may increase the level of flexibility within a supply network based on their expertise in coordinating and integrating the virtual supply chains and transportation networks. It is also argued that 4PL providers establish both sourcing leagility and leagile supply chain constructs, from the perspective of managing inter-organisational alliances. Limitations & Implications: The proposed framework may generally be applicable, although not without sacrifices. Practitioners would need to limit their service offerings to particular industry sectors and product categories. The framework neglects the coordination of 3PLs. Future research needs extend the sample of 4PLs to the fashion and beverage industry. Originality & Value: The thesis is a first attempt to integrate three different streams of research, namely, supply chain flexibility, the notion of leagility and the concept of 4PL. The thesis proposes a 4PL Leagility Framework that extends the leagility concept beyond the material flow decoupling point principle. Ultimately, the research illustrates potential approaches for 4PLs to facilitate leagile supply chain constructs.

Background – Increase in global competition, technological changes and demanding customers have resulted in more knowledge-intensive, unstable, complicated and an uncertain environment. In order to overcome these demand uncertainties and tough circumstances, manufacturers are required to investigate methods to increase flexibility. To achieve the flexibility improvements, each component of supply chain such as suppliers, manufacturing plants, warehouses, and distributors must possess the potential to be flexible. Theory implies that the main link between company’s upstream supply chain namely suppliers and its own business unit are the sourcing strategy. Usually sourcing practitioners distinguish between sourcing strategies using portfolio models. They normally categorize purchased items based on the strategic importance of the item and characteristics of its supply market. It is a critical issue to explore how different sourcing strategies, for different categories of procured items, can influence sourcing flexibility. Purpose– The purpose has been diagnosed as to study how the prerequisites of Bombardier’s procurement procedures along with its associated strategies, can affect the flexibility that can be provided through sourcing namely sourcing flexibility. This study desires to investigate the concept of sourcing flexibility with considerations on category level. It can be beneficial to investigate how different strategies, related to different categories of procured component, can influence the level of sourcing flexibility specified to that category. This would lead us to two key questions: How can sourcing flexibility be defined in Bombardier and why is it required? How can sourcing strategies influence sourcing flexibility considering different categories of components? Methodology– To provide appropriate definitions for sourcing flexibility and strategic procurement, this study went through a comprehensive review on the relevant literatures. By a deep analysis, accompanied with several unstructured interviews on one of the undergoing projects in the company, the drivers for the sourcing flexibility have been diagnosed. The procured components have been categorized into four categories of strategic, bottleneck, leverage, and noncritical through 4 different structured quantitative questionnaires. 33 diverse individuals with purchasing and/or engineering background answered those questionnaires. The categorization criteria have been extracted out from two models suggested by Kraljic (1983) and Olsen & Ellram (1997). Four independent components, one from each category, were selected for further observations. Finally, the links between sourcing strategies and sourcing flexibilities were expansively analyzed through 9 semi structured interviews with company’s strategic purchasers and suppliers’ representatives. Conclusion– Sourcing flexibility can be defined from two perspectives. First one refers to the capability of the focal firm to change the structure of its upstream supply chain. Second aspect refers to the ability of company’s suppliers to provide it with flexibility in three dimensions of delivery, volume and product. Both two aspects along with related dimensions can be measured in three different conditions of required, actual and potential by using range, mobility and uniformity as measuring elements. The results showed that the first perspective has a direct relationship to the sourcing strategies that focal firm may apply for different categories of procured component. Furthermore, the availability of second perspective is highly dependent on the relationship between the focal company and its suppliers, where strategic procurement plays an indispensable role. Based on the results the required level of sourcing flexibility, related to each category, differs significantly with other categories. The findings also suggested that the levels of delivery, volume and product flexibility have a close connection to the diverse strategies and attributes of the four different categories. Additionally they are well dependent on the internal operational capabilities of the suppliers along with the established relationship between buyer and supplier. Originality/Value– Main portions of previous studies have explored the concepts of sourcing flexibility and strategic procurement separately. Although, there exists some narrow numbers that have analyzed the relationship between sourcing strategies and sourcing flexibility to some limited extent. This study tries to contribute to the existing literature by empirically exploring the principal reasons for companies necessitating to increase sourcing flexibility. It investigates how sourcing flexibility can be improved through strategic procurement. The main contribution is to consider sourcing flexibility from the category perspective. Latter is a subject that has been neglected in the previous literatures. It is extremely hard to find literature which has analyzed sourcing flexibility at the category level. This report analyses the level of sourcing flexibility specified to different categories of strategic, bottleneck, leverage, and noncritical components. It suggests some factors that may influence the selection of a specific sourcing flexibility strategy regarding different component categories. Finally, it may introduce some extra elements that can be influential on the level of sourcing flexibility dimensions. Some examples of those influential elements are bargaining power and establishment of a close relationship.