Our fragmented health care systems are insufficiently equipped to provide frail older people with high quality of care. Therefore, we developed the Health and Welfare Information Portal (ZWIP), an e-health intervention which aims (1) to facilitate self-management by frail older people and informal caregivers and (2) to improve collaboration among professionals. The ZWIP is a personal conference table, accessible through a secure internet connection, for multidisciplinary communication and information exchange for frail older people, their informal caregivers and professionals. After development, the ZWIP was implemented in seven general practices, and this process was evaluated by means of a mixed-methods study. Eventually, 290 frail older people and 169 professionals participated in the ZWIP. Most professionals were positive about its implementation. Facilitators for the implementation were the experienced need for improvement of interprofessional collaboration and the user-friendliness of the ZWIP. Barriers were the low computer-literacy of frail older people, start-up problems, preferring personal contact, and limited use of the ZWIP by other professionals. In sum, this article describes the successful development and implementation of the ZWIP, an e-health intervention which can reduce fragmentation in the care of frail older people.