Luckily, I have quite a bit of previous team experience, and have faced this situation a few times in the past -- so let me tell you how I've learned to handle the issue. The most important first step in dealing with an underperforming subordinate or team member is honest communications -- talking with the person can lead to some surprising discoveries, such as the person not understanding the assigned tasks to being overwhelmed with the assignment. Once I discovered the problem, I could then forge a solution that usually solved the problem and allowed the work to move forward. So often in situations like this, the problem is some combination of miscommunication and unrealistic expectations.