In reflecting on which pieces of computer-assisted learning (CAL) stan
d out as strikingly successful, this paper argues that there are no ge
neralizations about what features of technology or software type makes
a piece of CAL successful, but that on the contrary the most definite
successes seem to come from a close fit between a piece of courseware
and its situation of use that is specific to that niche. These are us
ually cases where a teacher analysed what was particularly weak in an
existing situation and thought of how technology could be used to addr
ess that bottleneck. Often the technology is not particularly innovati
ve, but it is a close match to the needs of that niche. This paper dev
elops this argument by reference to a number of pieces of software whi
ch have little in common with each other, but all of which have proved
to promote learning powerfully. (C) 1998 Elsevier Science Ltd. All ri
ghts reserved.