E-Marketplaces for services are governed by similar, but not the same business and technology principles as e-marketplaces for products. Additionally, in the particular case of e-marketplaces for senior citizens, service innovation must be requestor-focused. Immobile (residential, fixed) and mobile ambient (sensors, actuators) intelligence devices cover the spectrum of people monitoring (daily living, health status). On the society side, the aim is to enable elderly people, nearing or in retirements, healthy or unhealthy, to live socially-included and economically-active lives. On the IT side, the aim is to provide innovative systems and solutions embracing contemporary shifts of computing paradigm to service science, cloud computing, mobile connectivity, business processes, and societal participation. In this paper the Authors present the service e-marketplace as an ecosystem that is able to utilize the capital of elderly people with the whole added value they can contribute. The special attention is put on integration of elementary e-marketplace systems which provide senior citizens with the specific kinds of services. The importance of the integrator entity is explained and the concept of information system that plays such a role is presented. Selected business and technological implications of embarking on the development of a service emarketplace platform for independent and assisted living are reported. The Authors discuss also plausible business models, identify major success factors, and present software engineering challenges underpinning development of such platforms.