DPMI may refer to:
In computing, the DOS Protected Mode Interface (DPMI) is a specification introduced in 1989 which allows a DOS program to run in protected mode, giving access to many features of the new PC processors of the time not available in real mode. It was initially developed by Microsoft for Windows 3.0, although Microsoft later turned control of the specification over to an industry committee with open membership. Almost all DOS extenders are based on DPMI and allow DOS programs to address all memory available in the PC and to run in protected mode (mostly in ring 3, least privileged).
DPMI allows a program to run in protected mode on 80286 series and later processors and make calls back to the operating system running in Real Mode. For example, a DOS program can "turn on" protected mode, but still make calls back to DOS for service (say, via the INT 21h standard DOS service interrupt). The most important reason for doing this is to allow protected mode programs to function under DOS, whose kernel used 16-bit real mode throughout its commercial life. Because MS-DOS (as a standalone operating system) was never updated for 32 bits, nor enabled 24- or 32-bit addressing, DPMI served as a "patch" to allow advanced protected mode programs to run on the stable MS-DOS platform. DPMI can be thought of as a "translator" that takes (for example) protected mode DOS calls and translates the registers to and from real and protected mode, including taking 16-bit segmented addresses and translating them to a suitable protected mode format.