for hospitals could be free of charge. Avoiding dangerous assumption traps with IPD: Today¿s planning information is based on too optimistic efficacy assumptions which are not coherent with reality in hospitals. Planning has to be more realistic to avoid dangerous ¿Assumption Traps¿ which lead to misdirected investments. Tracing imposed inefficiencies with Grey Performance Analysis: IPD focuses on externally imposed inefficiencies by targeting avoidable unnecessary work called ¿Grey Performance¿. Architectural consequences of IPD: IPD significantly influences the organizational structure, functional layout and architectural planning of complex buildings. Health facility architecture must change its focus from optimal use of surfaces to optimal use of human resources. Enabling more quality through additional revenues: More revenues are possible by surrounding building design with business design already in the early project conceptualization.