Nearly any competent engineer can plug in flash memory and make it work, but a well-designed embedded system also ensures data reliability. Flash is ideal for storing data in a mobile environment, however maintaining data integrity requires careful planning on the part of the designer. Reliable data storage on flash is not a simple matter of plug-and-play. Power interruptions and other hazards of embedded life wreak havoc with users’ data, often rendering it useless or inaccessible. As explained in this paper, the importance of a professional flash file system—the combination of a flash manager and embedded file system—cannot be underestimated.