We believe that a more rigorous method of specification and validation can be achieved by first developing a {\it specification architecture} whose high-level semantics are based on object oriented concepts. This architecture promotes the construction of new functionality in a formal manner using rigorous notions of composition and inheritance. An object oriented approach will also facilitate incremental approaches to validation and verification. We present our first steps towards producing such an architecture for the Plain Old Telephone Service (POTS), which is specified and validated using a formal object oriented language based on LOTOS. The method by which the formal model is derived from the informal understanding of the requirements is examined. Validation based on meta-analysis of the problem structure is elucidated.