A change is anything that impacts a project or task and necessitates an alteration in dates, scope or other aspect of that project or task.
These changes need to be managed intelligently: identifying when they are needed and when they are not, understanding the implications of the change to projects and milestones, and putting that change into practice - approving it, communicating it and ensuring it has been enacted.
The consequences of a poor change management process is the risk that milestones are pushed back without understanding how that impacts other milestones, causing cumulative and eventually damaging delays to the overall progress of your project delivery.
In a similar way to risk management, change management works best when it is predictive and proactive. An acceptance that your organisation needs to be adaptable is key.
It is also wise to build some contingency into your milestone plan, where possible, so that one change does not disrupt the entire baseline plan for a project.
Appoint a Change Manager role within your Project Management Office (if you have one), set up a simple mechanism for change requests, and go from there.
Why not read our full article on change management?