We evaluate the extent to which the distinction between semantically core and non-core dependents as used in the FrameNet corpus corresponds to the traditional distinction between syntactic complements and modifiers of a verb, for the purposes of harvesting a wide-coverage verb lexicon from FrameNet for use in deep linguistic processing applications. We use the VerbNet verb database as our gold standard for making judgements about complement-hood, in conjunction with our own intuitions in cases where VerbNet is incomplete. We conclude that there is enough agreement between the two notions (0.85) to make practical the simple expedient of equating core PP dependents in FrameNet with PP complements in our lexicon. Doing so means that we lose around 13% of PP complements, whilst around 9% of the PP dependents left in the lexicon are not complements.