Digital Research Inc says that Concurrent DOS 386 – the first multi-tasking, multi-user operating system supporting multiple PC-DOS 2.X partitions on the 80386, went on beta test last month, and will be generally available to OEM customers at the end of this month, and will be available to end-users in the second quarter of 1987. It supports the full 4Gb address space of the 80386 in native mode, and implements the ESM/LIM expanded memory specification in software, so that people running PC-DOS applications in the 8086 mode on the 386 can use expanded memory without special Above Boards. It supports CP/M-86 as well as MS and PC-DOS applications, and applications written to run in the native mode of the 80386. It supports up to 255 virtual 8086 tasks concurrently and incorporates task synchronisation. A window manager supports single-keystroke switching, and cut-and-paste between on-screen windows, and there is a GEM extension. A typical 16 users can be supported on a box using the 16MHz version of the 80386, and on the face of it, it is the ideal operating system for people wanting to get maximum mileage out of 80386-based Personalikes, but while Digital Research will win plenty of business for it in Europe, all the signs are that US manufacturers will wait forever for MS-DOS 5.0 rather than commit to the alternative.