Two production experiments investigating possible factors influencing the domain of final lengthening are described. Results indicate that final lengthening is generally confined to the final syllable, except when its rhyme contains only a schwa, in which case the penultimate rhyme is lengthened as well. Apparently, only the weight of the final syllable influences the size of the domain which is lengthened. Next, a perceptual acceptability experiment was run. Results indicate that while listeners are sensitive to differences in the amount of final lengthening, they are not very sensitive to the way this is distributed over the preboundary segments. Apparently, the specific distribution of final lengthening in production has no com-municative function, but is the result of the human speech mechanism, together with restrictions on the expandability of segments.