OK to recap from Part I and Part II now that Saturn has moved into Sagittarius (and this started loosely when he stuck his head in last winter, but more strongly recently when he unpacked his bags and kicked off his shoes and lasts through the end of 2017) he is squaring Neptune in Pisces (Sagittarius naturally squares Pisces - think pie chart here).
This square will be exact three times over the next 10 months, due to Neptune and Saturn retrogrades - Nov 26, 2015 at 7 degrees, June 17, 2016 at 12 degrees and Set 10, 2016 at 10 degrees. And remember even when an aspect is not exactly exact it may be still close enough, often for long periods, to be felt.
Squares are tense aspects - they push us into a new action (oppositions push us into a new decision, trines remove obstacles, sextiles show opportunities, etc). Everyone is going to work with this square before Saturn leaves Sagittarius at the end of 2017. Here's a post with info on Saturn in Sagittarius that could be helpful, too.
This is the big deal transit of 2016.