Interoperability frameworks provide specifications for different aspects of interoperability, for communicating and sharing information. Ten prominent industry-neutral interoperability frameworks are analyzed in this paper, distinguishing between operational interoperability frameworks and conceptual interoperability frameworks. To support this analysis, 16 criteria were defined, which represent the basis of a comparison framework. The operational interoperability frameworks analyzed have similarities and differences, and complement each other in some aspects (e.g. messaging service). The differences refer to the manner they handle (or not) different interoperability details relevant for performing e-business, e.g. only ebXML provides guidelines for negotiation and setting-up a collaboration agreement prior to conducting e-business. The five conceptual interoperability frameworks were analyzed based on specific structural elements, as they tackle differently the notion of interoperability, i.e. targeting types of integration, interoperability barriers, levels of interoperability. Despite the advances of interoperability frameworks, full interoperability is not yet achieved. The analysis performed allowed to conclude that although interoperability frameworks represent a good direction towards seamless interoperability in a networked environment, a big challenge is the harmonization of different aspects of the interoperability frameworks towards attaining full interoperability in complex cross-sectorial e-business scenarios, which can be addressed by joint actions of the scientific community and practitioners. Finally, this analysis yields a set of directions for future research work.