Optimization and Waste Management: The PIPER project The PIPER project enhances scientific research in the field of optimization and artificial intelligence applied to circular economy, with a focus on the territorial context of the Lazio region, Italy. The project's activities are directed towards the study and development of an intelligent platform for data analysis and strategic and operational planning of recycling processes for materials from both the industrial sector and urban activities. The PIPER project is an application of the urban intelligence paradigm as elaborated by the DIITET department of CNR (http://www.diitet.cnr.it/urban-intelligence/), incorporating various initiatives that have developed and applied concepts such as digital twin, optimization, and artificial intelligence to the urban context. The project activities have engaged stakeholders from the sector in different phases of the project, including the specification and design of decision support models, for usability testing, experimentation, and results analysis. During the seminar, the three models developed within the project will be presented. These models will allow (i) the planning of logistics for waste collection activities, (ii) the analysis of the main cost drivers of the collection network, considering the uncertainty and variability to which they are subject, and (iii) the design and reengineering of the regional waste collection network. These models could be made available to logistics operators in the sector, municipalities, and municipal companies.