Multi-source agreement: A term used in electronics (and possibly elsewhere) to connote an agreed-upon set of physical dimensions and pin-outs. The idea is to make companies' products interchangeable -- in terms of size and shape -- which theoretically will help speed the adoption of new technology.

This is because without an MSA, board designers have to pick their components ahead of time and build the board to those components' specs. This keeps the board maker locked in to that particular component vendor, and it also keeps the vendor's prices high. With an MSA the board maker gets more choices, which can help drive down prices because all vendors are now competing.

Most important is that the board maker doesn't have to worry about the component supplier going out of business or running short of supplies, because comparable parts are available from other MSA adherants.

For vendors, the benefit is that they actually get to sell parts; some customers won't buy unless your parts are replaceable by a second source. You also, theoretically, get to tap into a bigger market, because MSAs make designing easier for board and systems manufacturers, which in turn encourages more companies to get into that particular market. Theoretically.

Negative side-effect: MSAs also create the opportunity for companies to put out big-deal press releases about how their new part conforms to the MSA.