This article discusses the multi-threaded and multi-dimensional process of preparing a technical designs that lead to the introduction of new forms of use into existing urban and architectural structures of high historical value. It covers research concerning formal and spatial determinants, associated with local law in selected European countries. Its results point to concise, precise and easily understandable provisions in terms of local law concerning planned development in areas under heritage conservation, which is conducive to a climate of social acceptance of constraints and prohibitions that — some — may consider significant.