Observations from space missions are helping us understand phenomena within the Solar System. The greatest benefit can often be achieved if data from the many observatories are combined but this is not always as easy as it should be. We have been examining ways in which this situation can be improved. The CASSIS project is coordinating efforts to achieve greater interoperability. The HELIO project provides a unified way of accessing data from many domains and the tools to make intelligent decisions about which data may be of interest and relevant as phenomena propagates through the Solar System. Europlanet RI provides a more integrated approach to data related to planetary science and the IMPEx project is developing techniques that allow models and tools related to planetary environments to be used together. Our objective is to find ways that combine these efforts into a collaborative research environment for Solar System science. We have been examining the purpose and interfaces of services developed by the projects and considering how they might be used together to address more complex science use cases. The projects all employ registries of one form or another that are either compliant with or very similar to IVOA standards but differences in the science require a detailed examination of the specifications. The nature and mix of services used in Solar System science differs from other parts of astrophysics because we are immersed in object that we are observing; also, the way that the services of HELIO are deployed places additional requirements on the registry. In collaboration with CASSIS, the projects are trying to determine how the efforts can be aligned and whether extensions to IVOA standards are required. Greater integration will be possible once we have achieved a unified approach to registry description of the services that support Solar System science. The communities involved use different file formats, including FITS, CDF, ASCII. There are differences in the terms used to describe the file contents although the underlying meaning of the parameters is often quite similar and we have also been investigating whether the files can be made more interoperable so that the available tools can be used more widely. We are examining two approaches to this problem: i) we are exploring whether an external but associated “style” or “definition” file could be used to more completely describe the meaning of the header information of files and afford a way to map terms into a more standard name set; ii) we have been experimenting with the semantic mapping techniques to see if it can achieve the required result.