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Qualitative relations between spatial regions play an important role in the representation and manipulation of spatial knowledge. The RCC5 and RCC8 systems of relations, used in the Region-Connection Calculus, are of fundamental importance. These two systems deal with ideal regions having precisely determined location. However, in many practical examples of spatial reasoning, regions are represented by finite approximations rather than known precisely. Approximations may be given by describing how a region relates to cells forming a partition of the space under consideration. Although the RCC5 and RCC8 systems have been generalized to “egg-yolk” regions, in order to model certain types of vagueness, their extension to regions approximated in this way has not been discussed before. This paper presents two methods, the syntactic and the semantic, by which the RCC5 and RCC8 systems may be defined for approximate regions. The syntactic uses algebraic operations on approximate regions which generalize operations on precise regions. The semantic method makes use of the set of precise regions which could be the intended interpretation of an approximate region. Relationships between these two methods are discussed in detail. alternative to navigation training with a map.