**5. Discussions and Limitations**

For solving complex real-world sustainability problems, as outlined above, it is vital to bring together a broad range of researchers, practitioners, and stakeholders with a shared vision and goal. Collaborative research endeavors are challenging since this requires cooperation across disciplines and scales; therefore, the effectiveness of such research can be hard to measure in the short-term. At the same time, we regard the network that the project was able to build so far and its communication strategy as a major contribution toward a potential solution. Bringing stakeholders from the physical sciences, the social sciences, and the health sciences, as well as non-governmen<sup>t</sup> and governmen<sup>t</sup> representatives and practitioners, in our case, the jeepneys driver association representatives, together to discuss air pollution is a novelty in itself. To then follow a systemic approach in which the problem was collectively defined and agreemen<sup>t</sup> on the search and development for potential solutions was achieved is the basis for further collaboration. The Department of Transportation, a major stakeholder, agreed to work closely with the team and to become a part of it. In Figure 4 below, the TRANSFORM and FTI approaches applied for TAME-BC are displayed. Assessment and analysis (step one of the TRANSFORM approach's requirements) of the air pollution levels (Port, Quezon City (QC), and background BC levels) is the work conducted in pillar one. In pillar two, by incorporating de jure governance responses by state institutions and de facto mechanisms of the public, we study past and current states of the environmental problem (step two of TRANSFORM: provide solution-orientated goals that reflect the current state of the problem). Pillars three and four contribute to the mitigation of the air pollution problem by building awareness among the PUJs and by involving important local stakeholder networks. Pillar four is crucial for local embedment. The fourth pillar ensures that solution-oriented results from all other pillars are locally adopted and embedded in Metro Manila (step three of TRANSFORM: contribute to mitigating the current (pollution) problem).

**Figure 4.** The "follow the innovation"(FTI) and TRANSFORM methodology steps displayed using the four pillars of the TAME-BC set-up.

For solving sustainability problems, tailor-made approaches are needed. Since every scientific attempt has a di fferent method for tackling sustainability problems, it is hard to compare the methodologies. The state of the art on transdisciplinary research processes for more sustainability is still in the early stages. Although there is a growing number of publications on the topic, it is not possible to compare the research setup in this manuscript with a similar scientific approach in the past. TRANSFORM and FTI provide a scientific basis for conducting air pollution mitigation research. Nevertheless, due to changing local conditions and di fferent sustainability goals, no comparable scientific approach has been taken before, according to the knowledge of the authors. If a similar scientific transdisciplinary approach emerges in the future for addressing sustainability problems, it is recommended to compare the results and e ffectiveness of the practices applied.
