In the world where on-demand and trustworthy service delivery is one of the main preconditions for successful business, availability of the services and business processes is of the paramount importance and cannot be compromised. We present a framework for modeling business process availability that takes into account services, the underlying ICT-infrastructure and people. Based on a fault model, we develop the methodology to map dependencies between ICT-components, services and business processes. The mapping enables us to model and analytically assess steady-state, interval and user perceived availability at all levels, up to the level of the business process.