This is a great question, Susan. When tasting several different vintages from the same producer, most professionals begin with the oldest vintage. The reasoning is that the oldest wine is likely to be the most integrated and nuanced, and possibly the most frail. The youngest wine is likely to be the boldest. If you taste the young bold wines first, you may not be able to fully taste the nuances of the oldest wine when you get to that wine. So most pros start with the oldest wine.