I've been reading a lot of online articles lately that claim the answer to your bully problem is the implementation of a corporate policy. Even BusinessWeek is guilty.
We can implement policies all day long, but unless they are in alignment with the organization's overall vision and have leadership buy-in it will be like they don't exist at all. Corporate policies are only as good as management and employee support for them.
That means we must adjust the corporate culture and obtain buy-in from everyone (or at least as many people as possible) before we can create a corporate policy that fits within the new, and nice, way of doing things. If the anti-bully/healthy workplace policy is to be effective, it will decidedly be designed to achieve the newly established vision and culture. (In other words, corporate policies do not adjust corporate culture, but they can be used as a tool in the process.)
One sure fire way to gain employee support is to get them involved in developing the vision of a healthy culture and corresponding policies. If staff helps create the vision, it's easier to hold them accountable to it. And when they feel included in the process, they are more likely to take heed to it anyway simply because they have a vested interest in doing so. In addition, when employees are involved their personal values are involved, thereby individual values and corporate values become one in the same.
Asking departments to develop action plans surrounding the new vision is also useful in obtaining support. Action plans are documented procedures directly related to meeting the new business strategy; and list the actual steps, responsible individual, resources required, measures for success, due date and actual date of completion. For example, a department might decide to perform a specific project as a pointedly collaborative team; tracking their success, how well they work together, and the accountability of each team member. The results would then be reported to management and perhaps the entire organization for accountability.
Appointing organizational champions can also be helpful. Employee assistance professionals, ombudsman, and even plain ol' employees can fill these positions. Organizational champions would then be responsible for ensuring people are treating one another with civility, respect and encouragement. Champions should also be part of the policy roll-out process in order to obtain their full support of these new responsibilities.
So, don't add an anti-bully corporate policy to the policy handbook and expect the bullying behavior to stop. If no one supports it, then who cares. Bullying behavior will stop when the corporate culture doesn't allow that type of behavior to thrive anymore... and that goes way, way beyond anything a corporate policy can do. Adjust the company vision, and then implement a policy in-line with the new way of doing things.