Information systems integration has been our core business since early 1990s when we delivered our first solution to health care. Times and technologies have changed, but the basic challenge has mostly remained. We architect, develop, and of course support integrations between any kind of information systems. Currently our best experience is working with health care (HL7 and others), ERPs (SAP and some others), and mobile operator back-ends.
The main toolset we use today for integrations is Apache ServiceMix. It is very high quality, widely used, offers good support for 100+ sources and destinations, and having free license makes it cost efficient. Although many of our solutions use Apache ServiceMix as the engine, some integrations are still developed as point solutions without it.