The rapid growth of the ageing population has sparked great interest in technology-supported aged care to achieve more effective personal care solutions that address older adults’ emotional, social, physical, and mental well-being. Existing uses of Requirements Engineering (RE) for ageing users’ digital health solutions have identified, elicited, and prioritized stakeholders’ needs, but show significant variation across studies, affecting the quality and depth of requirements gathering to date. Inconsistent adoption of RE techniques creates gaps in understanding and realizing older adults’ specific needs in their digital health solutions. In this thesis, I aim to improve requirements engineering approaches for understanding, gathering, and modelling diverse human aspects of elderly end users in digital health software. The main goal is to better understand and use these requirements for innovative future personalized care solutions. This research will enhance the well-being of elderly end users by improving the RE process to better capture diverse human aspects of older adults in digital health software for personalized care systems.