Companies do not underestimate the strength of their employees’ social contacts. Just the opposite, they’ve begun to reward them if they help bring new and skilled help into the firm.
Every employee knows someone who knows someone else, and their neighbour has a guy who’d be perfect for a specialised position in your company. Maybe they aren’t actively looking for work, but your employee’s efforts open their eyes to a job opening and they get to thinking.
More information: http://www.recruitingblogs.com/profiles/blogs/why-companies-do-not-underestimate-the-strength-of-their