This chapter focuses on interventions in physical healthcare/residential care environments in order to support person-centered and safe care for older people. The chapter discusses the mixed method research design to increase the knowledge base and follow up of outcomes of these interventions. The chapter has a nursing care perspective with a basis in the notion that the physical environment represents an important part of the nursing care. The resources and disabilities following old age should be the starting point when designing environments for older people to minimize unwanted behaviors and feelings and maximize desired ones. But how can we even further adjust the physical environment to support and to promote perception, attention and orientation, and in turn reduce stress? The aim is to contribute with evidence- and practice-based knowledge to support the developing of caring environments for older people that puts the persons and his/her demands in focus. A place where it is easy to reside, where the older people and their family members are being welcomed, can recognize themselves in the environment and feel safe, and where staff can take pride in the care given and feel satisfied with their job.