“Tiers” are used to designate support agents of varying degrees of experience and expertise, as well as to refer to the types of work done by those agents. Tier 1 agents handle basic issues, such as resetting passwords or recovering forgotten license keys. Tier 2 agents handle knottier support issues, many of which can’t be resolved by simple steps or non-decision tree automated solutions but require intricate diagnoses and creative approaches. Tier 3 is the last resort for problems that couldn’t be handled by Tier 2 agents. In many companies, Tier 3 agents aren’t professional support reps at all, but engineers called upon on an ad hoc basis to tackle the rarest and toughest problems.