Contrary to claims in the literature, the "P NMR signal positions of ortho-dimethylaminomethyl-substituted triarylphosphines do not provide evidence for hypercoordination at phosphorus; the observed highfield shifts relative to triphenylphosphine are rather due to the ortho-effect. In (8-dimethylamino-naphth-I -yl)phosphines, the signal positions similar to that of triphenylphosphine are the result of the highfield orrho-effect and a lowfield peri-substituent effect of about the same magnitude whose nature remains to be explored.