The global amount of waste generated by households, including food packaging waste, has been increasing continuously across the world, posing a massive threat to societies and the environment. Proper waste management, therefore, has become a challenging environmental issue and a priority for governments. Along with the technological advances, such as material recovery technologies, more stress has been placed on the strategies for moving away from disposal to waste prevention, separation, and recycling. Considerable efforts are being made to not only limit the overall production and the negative impact of waste on the environment and human health but also to minimize the cost of waste management. Separation of wastes at the source (i.e., source separation) is an integral part of such efforts toward enhancing the purity of collected waste and improving the quality of materials for recycling. Furthermore, sorting of waste as a habitual performance can serve as a practice for improving residents' recycling/sorting behavior. The packaging waste, including food packaging, forms a significant part of the municipal solid waste. The design of food packaging, therefore, has received a lot of attention as a useful tool to influence the consumers' sorting behavior, making it an interesting concept for research related to waste management. Presumably, the design of food packaging can meet consumers' sorting demands while being instructive and facilitating the sorting process, thus enhancing the recycling rate of the food packaging waste. Finding the ideal form of food packaging, however, requires an in-depth understanding of the packaging-consumer interactions throughout the sorting process. Considering the different characteristics of food packaging, it is expected that different food packages tend to influence a consumer in different ways. Nevertheless, the current knowledge is somewhat too general to be used by packaging developers to improve the sorting of the food packaging. Hence, the present thesis aims to provide a more in-depth insight into the influence of food packaging, as a product and service provider, on the consumer's/user's decision-making on sort of food packaging waste. The results assert that packaging to be sorted properly requires proper design to manifest its sorting related abilities such as easy to empty, easy to clean, and easy to fold, for the consumer. Selecting material, visual attributes, form, and function can amplify or reduce these sorting abilities of food packaging.

Due to population growth, urbanization, higher income levels, and intensive use of packaging products, the amount of waste generated by households, including food packaging waste, has been increasing continuously worldwide, posing a massive threat to societies and the environment. Therefore, proper waste management has become a challenging environmental issue and priority for governments. Along with the advances in technical aspects, such as material recovery technologies, more pressure has been placed on the strategies to move from disposal to waste prevention and recycling. Considerable efforts are being made to limit the overall production and the negative impact of waste on the environment and human health, as well as minimize the cost of waste management. Separation of different waste fractions at the source (i.e., source separation) is an integral part of such efforts toward enhancing the homogeneity of collected waste and improving the quality of materials for recycling. Sorting waste as a regular activity can also serve as a practice for improving residents' sorting behavior. However, the benefits of source separation cannot be gained without actively participating in the sorting process, which depends on the perception of convenience and the easy-to-implement nature of the process. Therefore, the design of food packaging has become an interesting concept for research and has received a lot of attention as a means to influence the consumers' sorting behavior. This is because in some way, consumer behavior is shaped by products as much as products are shaped by consumer behavior. Considering the unique characteristics of food packaging, it is expected that different food packages tend to influence a consumer in different ways. Hence, applying proper design strategies requires an in-depth understanding of packaging-consumer interactions throughout the sorting process. However, the research in this field, except for a few, is too general and usually associated with the impractical experiences around packaging material and functions. Instead, a design-oriented approach should be considered, in addition to practical experience. This thesis, therefore, aims to unfold the packaging design potential to support sorting behavior. Furthermore, how is it possible to maintain and empower the user-packaging interaction by applying different design strategies? In this case, the potential of design approaches, namely the user-centered design (UCD), design for sustainable behavior (DfSB), and design affordance, have been discussed. Moreover, the advantages and opportunities of these methods to improve packaging design, thus influencing sorting behavior, are investigated using different research methodologies.