One thing to remember about sexual harassment: it is about power, not sex. Victims are usually highly avoidant and unwilling to report such instances, which is why a large percentage of sexual harassment claims go unreported. In situations where you have a serial harasser, such claims may not come out of the woodwork until years after one employee or former employee comes forward. Clients and customers can be harassers as well.
Which issues can you handle on your own? When should you contact an attorney? Once a claim of harassment has been made by an employee, do you understand what your responsibilities are? You need the knowledge and resources to conduct a prompt, non-biased, and complete investigation, or you risk making the situation worse.