Every brewery should consider a brand “refresh” every so often. Even seemingly “unchanged” brand graphics like Sierra Nevada Pale Ale have gone through numerous design changes over the years. The first step in a brand refresh is to work with a design company. Craft Brewing Business has released a 10-minute video on how to work through the proposal and contracting phase when hiring a design firm to handle your rebrand.
Various conversations on marketing here on the ProBrewer Discussion boards.