This study discusses the relationships of material things to people with dementia and proposes the development of material environments to enhance their well-being. Integrating research on well-being from existential, ecological, and place-based perspectives, this study develops a new understanding of the well-being of people with dementia when considering the active role of material things in the process of developing well-being. “Well-being of people with dementia” refers to the awareness of self-existence in a real-world environment established by the interactions of people and material things. Based on this understanding, this study integrates four types of environmental embodiments, including obliviousness, watching, noticing, and heightened contact, providing specific guides to understand people’s associations with their material environments. An environment-based conceptual framework, based on the new understanding of the meanings of well-being and its association with material things, allows designers and professional/family caregivers to understand the lived experiences of people with dementia, in order to enhance the well-being of their clients and their families by using material things to create a more holistic environment.