Reminders
At any point you can specify how long a person to whom a form has been routed, has to respond. Once the basic response period has elapsed you can instruct the system to send reminders.

Escalation
Once the specified number of reminders have been sent out and if there is still no response then you can instruct the system to escalate the form to the System Administrator or to the person's manager.

Delegation
Quask WorkFlow software also has a delegation facility that allows each person to maintain a delegate list. Delegates can handle a form if someone is away from the office or fails to action the form on time.