Finding Regions for Local Repair in Partial

In contrast to standard constraint satisfaction problems (CSPs) practical applications often require both, the management of changing validity of constraints and variables. Based on experiences made with the development of a commercial nurse scheduling system this paper suggests the application of local optimization algorithms for knowledge-based conngura-tion systems, which strongly rely on dynamic constraint management. The main contribution is a small theory on how to enumerate the regions (a set of assignments) in a partial solution to a constraint problem, which have to be changed in order to obtain a global solution. Such a theory enables the application of local repair mechanisms to knowledge-based systems. Presented at the CP'97 Workshop on \Theory and practice of dynamic constraint satisfaction"