Try a 3x3 rule for account management
Many times salespeople find that they are able to build deep relationships with a project champion at a client site, but they don't often interact with other potential decision-makers. This may work quite well until that project champion, leaves or moves from the position. In order to insulate your relationship with client organizations, use a "3 by 3" rule. Make contact with at least three individuals at three different levels in the organization. That way you will be more in tune to other opportunities and can prevent being locked out of major accounts in case your main buyer leaves.