The MCM Designers' Access Service (MIDAS) allows designers to obtain prototype and small quantities of MCMs. To date the service has processed designs from industry, government and major universities. The service currently accesses processes at the following MCM-D foundries: nChip/Flextronics in San Jose, CA; Micromodule Systems in Cupertino, CA; and IBM Microelectronics in Hopewell Junction, NY. MIDAS provides a low cost service achieved through a multiproject environment where the customers share tooling and substrate manufacturing costs. The service offers design support, distributes foundry design kits, groups the projects onto regularly scheduled runs, places orders and supplies fully assembled modules. As well, MIDAS offers a limited selection of open tooled, second-level packages, bare tested die, and test sockets to aid with the design process. Often when investigating implementation of MCMs into a working system designers need a prototype. In many cases a foundry prefers to handle only high volume orders or imposes minimum purchase quantities. These may likely exceed the entire project budget. MIDAS functions as a technology enabler by supplying the designers with an interface `transparent' to the fabricator and common to multiple vendors. Foundries prefer to work with a single source who coordinates the details of multiple orders to spare valuable overhead. By completing front-end foundry tasks such as data preparation and mask fabrication and by grouping multiple users together on a run, MIDAS serves this purpose. Certain design conditions such as footprint size and I/O ring, layer stacking and number of layers exist to establish uniformity amongst the unrelated customers. This paper discusses the history of the service, the operating guidelines and presents an overview of how to access the service for MCM fabrication.