## 7 Discussion
### Operationalizing the SPP Toolbox in the STP Model  
With the aim to foster the transformative potential of procurement to contribute to socio-technical transitions for sustainability through niche formation and therein using the GPP, SPP and PPI approaches in particular, a new tool to guide public organizations has been developed. The development of the SPP Toolbox involved a participatory process: the tool was presented and discussed in meetings with key Portuguese stakeholders, including the organizations participating in the three case studies. In general, the SPP Toolbox was assessed as a relevant and useful management tool, with an adequate structure and flexibility. However, it was pointed out that the main barriers to implementing the SPP Toolbox are the mind-sets of the organizations, shaped by the current regime and landscape and the time and resources needed. Designing and developing the SPP Toolbox required assembling a broad range of perspectives, for completeness, while combining it with a logical structure, through the use of the GPP Management Model, proposed by the European Commission [52] and ICLEI [33; 34]. Furthermore, it required developing practical skills concerning key factors proposed at the niche level of the STP Model, as mentioned in Section 5, namely: individual factors, management factors, procurement factors and inter-organizational factors. Individual factors focus on the role of individuals within the organization and the key factors identified were \"change agents\" and \"knowledge\". Change agents refer to willingness to change, motivation, ambition, commitment and the role of individuals as champions, facilitators and leaders [5; 14; 16; 24; 26; 30; 45; 60; 61] and are developed in Step 1, while defining the responsible team. Change agents are then further operationalized in the \"people\" dimension of the SPP Diagnosis Matrix, which involves the definition of targets related to personnel performance indicators (Step 2),  
Figure 6: Evolution of SPP Diagnosis Matrix for LIPOR. action plan definition (Step 3) and implementation of the action plan (Step 4). The \"knowledge\" key factor, which accounts for skills and training [1; 5; 16; 18; 20; 43; 45; 61; 62; 1], is also developed in a similar way in the \"people\" dimension of the SPP Diagnosis Matrix. Management factors cover organizational culture, strategy, internal change, internal collaboration and responsibilities. Organizational culture maps out informal cultural attributes of the organization [14; 24; 30], developed in Step 2, in the definition and approval of the SPP policy. This is also reflected in the setting of targets for the \"policy, vision and targets\" dimension of the SPP Diagnosis Matrix (Step 2), which is then translated into the action plan in Step 3. Step 4 is particularly important for the operationalization of this key factor, as it includes the collection of difficulties and lessons learned during the implementation of the action plan, contributing to the embedded organizational learning and hence to this key factor. Additionally, organizational culture is reinforced in Step 6, regarding new measures for overcoming any obstacles identified. Strategy is developed in the priority products and services definition in Step 1 and across the whole of Step 2, including the \"Policy, vision and targets\" dimension of the SPP Diagnosis Matrix, which is then translated into the action plan, in Step 3 and implemented in Step 4. These steps fully operationalize the procurement strategy, allowing alignment with the corporate strategy and the development of an internal vision for solving societal problems [14; 17]. The key factor \"internal change\" is related to the promotion and management of a flexible organizational structure [5; 15; 26; 30; 45] and it is therefore developed within the definition of the responsible team, in Step 1, which involves creating an adaptation group to facilitate the process of change.