The service-oriented paradigm constitutes a promising technology that will allow many software systems to benefit of interesting mechanisms such as late binding and automatic discovery. From a service integrator?s perspective, it is relevant to understand service evolution, to assess which could be its impact on his/her own system or, eventually, to change the bindings between the system and the services. Given the lack of source code availability, this task is, however, limited to understand how service interfaces evolve.

We propose an approach, based on Formal Concept Analysis, to understand how relationships between sets of services change across service evolution. The concept lattice is able to highlight hierarchy relationships and, in general, to identify commonalities and differences between services. Examples built upon real sets of services show the feasibility of the proposed approach.