## 5 Conclusions  
This study reviewed literature works presenting practical ways to control indoor environment based on thermal comfort analysis. Journal articles and conference papers were searched in the Scopus database limited to the five-year period between 2017 and 2021. The analyzed papers showed clear trends both in thermal comfort analysis and in control strategies. PMV is the dominant framework for the prediction of thermal comfort, although often with simplified formulation or input assumptions, especially concerning personal factors and mean radiant temperature. Data-based thermal comfort evaluation is the most frequently used non-PMV approach. This choice corresponds to a growing attention towards personal preferences, and already finds implementation in prototypical studies. The applicability of another popular approach, adaptive thermal comfort, was found to be explored also outside of the contexts recommended by the reference standards--for example, some studies utilized it even in the presence of mechanical systems. A vast majority of the studies focused on thermal-comfort-based control of air conditioning, followed by hydronic systems. Not surprisingly, the preferred control variable is indoor temperature to be used as a thermostat set-point, although it was not always clear whether it referred to air temperature or operative temperature. Concerning control aspects, the methods to calculate control settings range from expert rules to complex modeling techniques such as machine learning and model-predictive control. Overall, two-thirds of the analyzed papers include one or more optimization steps carried out with one of the several methods available in the literature. In general, it was found that many studies on innovative control systems are still at a simulation level. Office or commercial buildings with air-conditioning systems were the most investigated environments; the reasons are probably linked to higher available budget, more advanced monitoring and control infrastructure, desire to increase productivity, and perspective of energy savings. The number of journal papers and of works presenting prototypes has increased through the years, proving that this research area is vital and that it is moving closer and closer to field deployment. However, some categories of vulnerable people have special needs that are only beginning to be investigated and will require more research effort. The wide variety of analyzed studies shows that there is no one-fits-all solution to the problem, but many options are available and more will follow. The key is putting it all together: the synergy between building and HVAC designers, energy saving experts, and thermal comfort specialists, who still tend to work separately, could be the real breakthrough in the definition of pleasant sustainable indoor environments.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app12115473/s1](https://www.mdpi.com/article/10.3390/app12115473/s1)]([https://www.mdpi.com/article/10.3390/app12115473/s1](https://www.mdpi.com/article/10.3390/app12115473/s1)), Spreadsheet S1: Full-featured database of reviewed papers.  
**Author Contributions:** Conceptualization, B.G. and E.A.P.; methodology, B.G.; formal analysis, A.M.L.; investigation, B.G. and M.P.; writing--original draft preparation, B.G.; writing--review and editing, E.A.P., A.M.L., and M.P.; visualization, B.G.; supervision, M.P. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received no external funding.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The data presented in this study are based on the spreadsheet available as Supplementary Materials.  
**Conflicts of Interest:** The authors declare no conflict of interest.