The preceding chapters touched only occasionally on the pedagogical implications of studies of transfer. In comparison with research twenty or thirty years ago, second language studies now tend to show more caution about what conclusions teachers should draw from any particular set of findings. This caution reflects a growing awareness of the complexity of transfer and other topics in second language research. Accordingly, many researchers would now hesitate in dispensing prescriptions for the classroom, especially since very little of the advice one might give has been thoroughly tested. Yet despite the commendable caution seen more and more in second language studies, some of the research on transfer does have implications for teaching that merit discussion.

The most important implication is that cross-linguistic influence has considerable potential to affect the course of second language acquisition both inside and outside the classroom (cf. Section 9.2). As Schachter (in press) observes, there is far too much evidence for anyone who looks closely at the empirical record to be skeptical about the significance of transfer. It is true that much uncertainty remains about many issues related to cross-linguistic influences, and it is undeniably true that researchers are far from able to predict with full accuracy when transfer will occur (cf. Section 9.3). However, it is also true that skeptics are far from able to predict when transfer will never occur.