Bringing many tools together to build a system of co-operating OAIS's in the MathArc project. The MathArc project has created a protocol, software, and registry that enable multiple institutions to share and store digital objects in each other's OAIS repositories, regardless of the nature of each system's underlying repository. In the pilot version, the Goettingen State and University Library (SUB) and the Cornell University Library (CUL) are sharing, storing, and managing collections preserved in Goettingen's kopal system (based on DIAS) and Cornell's CUL-OAIS (based on aDORe). The tools and standards used to build the system are familiar to those working in the digital preservation field and have been described and presented in many places. They include METS, OAI-PMH, PREMIS, JHOVE, LOCKSS, aDORe, and the kopal version of DIAS. This presentation describes not how they work individually, but how they all work together in the MathArc system.