The theme of this article is that much SLA research would gain if it took a
ccount of its place within an overall understanding of the component parts
of this complex discipline and the relationship between them. In the articl
e I first provide comments on UG based accounts of SLA, functionalist accou
nts of SLA, and processing accounts of SLA. In each case I seek to examine
their specific contribution to an overall understanding of the discipline a
nd at the same itme to state the limits of that contribution. I also seek t
o examine whether the differences between these approaches derive fro funda
mentally contradictory beliefs or whether there is a degree of complementar
ity. In doing so, I argue in favour of a view which stresses complementarit
y, without seeking to deny the validity of underlying difference of opinion
. I argue that the major 'holes' in the discipline arise from the difficult
y of dealing with the way in which linguistic knowledge is created either t
hrough triggering or through the linking of conceptual knowledge to linguis
tic form. The missing element may be a failure to incorporate an awareness
of how processing and memory systems work. I examine the contribution of th
e limited number of accounts which do assign importance to processing and t
o memory before concluding that this is an area on which future research sh
ould focus.