Referees are your personal salespeople so you need to make sure you have chosen wisely and leveraged value from the conversations they will have on your behalf.
Your current workplace may be a no-go zone though a trusted colleague might speak for you without blowing that you are in the hunt. Former bosses are a staple but also consider peers in other workplaces; clients and customers; people who have trained you or been trained by you and personal contacts who know the industry.
