This book presents the refereed proceedings of the Fourth Italian Forum on Ambient Assisted Living (AAL), held in Ancona, Italy, in October 2013. A wide range of issues are covered, and new technological developments are described which will support the autonomy and independence of individuals with special needs through an innovative and integrated approach, designed to respond to the socio-economic challenges of an aging population. Topics addressed include: health and well-being, prevention and rehabilitation, and support for care providers; active aging and its social implications; services for the frail elderly with health problems and their families; nutrition; ICT platforms/technologies for the benefit of the elderly; home automation and control technologies (autonomy, safety, and energy saving); smart cities and smart communities; telemedicine, telerehabilitation, and telecare; mobility, participation, and social inclusion; games and fun for the elderly; building design; social housing; interface design and interaction (accessibility, acceptance); social policies to encourage and support active aging; business models, market analysis, and development of sustainable financing and business; and ethics, privacy, and data protection. Many experimental validations based on user trials and usability testing are presented and discussed. The knowledge and insights provided in this book will help researchers and others involved in AAL to understand relevant societal trends, novel technological developments, and pressing challenges.