5 fold?
I've not read too much by Frank Viola, but I know he's quite popular with some in thinking about organic church etc.
Just read his thoughts on "5 fold ministry" and apostles - it's a helpful article (here), especially the first bit describing the history of the notion of "restoring the gifts".
Not sure I buy into his "organic vs organisation" type contrast, although I should probably read more before judging (but it did remind me a bit of some of the stuff by Gene Edwards).