Finding Out Who is Impacted
Once you figure out the need for change and which members of your organization are being impacted, you can then move onto whom do you need to support the intended change. You need a pretty substantial support structure no matter how large or small the intended change is.
First of all, you need the support of your team. Helping them understand and buy into the change will increase your chances of success. Provide incentives for those that do accept the change. They are more likely to talk up the project and get many of their team members to accept it as well. You need to get a majority of those affected by the project to agree to what you are doing. If not, you are very likely to fail.
Plus, you need to make sure that the sponsor (the person who decided that the change was necessary) and all managers are on board. Most of your employees and teams will be looking to management for guidance. If these people don't embrace the change and their new roles, you are probably already in trouble.
It may help to develop a strategy for incremental change. You should start the change by instituting one phase of the change for a few months and then assess the effectiveness. If the current project is successful, then you can institute the next phase of your change management methodology. Using Change Management Methodology to Deal with the Risks of Change, explains in detail the relationship between change and risks.