## 2 Theoretical Framework  
### Missions and Innovation Systems  
Mission-oriented innovation systems (MIS) are a recent approach to provide an analytical framework to analyze mission-oriented innovation policy (MIP). The MIS approach may be conceptualized as a merging of innovation system theory and MIP. [PERSON] et al. [5] defined MIS as a \"_temporary innovation system in which policymakers and other actors aim to coordinate innovation activities, with the objective of developing a coherent set of technological, institutional and behavioural solutions_\" [5]. Hence, MIS focuses on the innovation system surrounding goals that are set to complete a societal mission, or, in other words, the innovation system that becomes established via an MIP. MIS differs from other innovation system theories by focusing on the system around a problem rather than on that behind technological innovations, as does the technological innovation system (TIS). In addition, the boundaries of an MIS are set based on the societal challenge it tries to tackle, instead of the regional or national boundaries (RIS or NIS). Such systems perspectives for analyzing innovation processes also support demand-side innovation policies, facilitating analyses of interdependencies and interactive learning inherent to innovation procurement [26], of which GPP is a subtype.  
Ideally, \"missions\" give a sense of both urgency and meaning' while expressing values that citizens care for [5]. As discrete locales where practical change can be implemented toward grand challenges such as climate change, municipalities have close proximity between buyers, firms, and users which facilitates knowledge exchange toward the public procurement of innovative goods and services [18]. [PERSON] et al. [27] refer to this knowledge exchange in the local ecosystem as \"conversations\" [27] in support of innovation procurement, as facilitated particularly by their close physical proximity. Intermediary roles to facilitate such knowledge exchange between buyers and suppliers can take the form of facilitating, networking, and brokering, as identified in the challenge-driven Startup-in-Residence (SiR) program of the Municipality of Amsterdam [28].  
Central to innovation systems approaches such as MIS is the role of stakeholders in furthering the system as a whole through their various interactions that drive it. For the purposes of this paper, the definition of _stakeholders_ by [PERSON] [29] is adopted, as a \"... group or individual who can affect or is affected by the achievement of the organization's objectives\". Recent analyses using stakeholder theory in GPP have subcategorized these into _internal stakeholders_ and _external stakeholders_[30], with the former including the GPP project team and administration, and the latter including local government and the public. Focusing particularly on the role of external stakeholders in driving GPP practices, [PERSON] et al. [30] used stakeholder theory to examine 142 local public sectors in China, finding that administrative stakeholders within the public sector can mediate effects of knowledge of GPP implementation policies and benefits. Investigating instead a wider variety of stakeholders, [PERSON] [31] examined the interactions of stakeholders across the procurement planning phase of a pilot project in the Netherlands, finding that stakeholder alignment is critical to a GPP project's success and can be facilitated via _intermediary_ stakeholders with various types of project-relevant skills.