This paper presents research in Pan-European Public Services (PEPS) and Pan-European E-Government Services (PEGS). We examine different types of semantic interoperability issues that may arise when actors, information and services from different Member States (MS) need to cooperate and/or interoperate during the public service provision process. The semantic conflict types that arise in these cases are identified and classified according to a typology that is based on the combination of a known classification for semantic conflicts and domain specific concepts from the Governance Enterprise Architecture object model. This conceptual modelling describes and organizes the problem space, documents the requirements and can thus provide the basis for engineering solutions to resolve the identified conflicts.