The current company that I work for uses ECOs in the form of change notices as Julienne has stated above. The process of implementing a change within an SOP requires engineering to supply a redline and final draft of the suggested changes to document control via a software format known as a CN. Once the CN is approved by document control then only will it route for an approval from one designated reviewer from Regulatory, R&D, Manufacturing and Operations. Then only will document control release the new revision for others to access. However, if the change affects the design input or output of a medical device or procedure then it will require a design change. A design change has four phases, each phase will result in a design review meeting and approval by a design review board. Only after the fourth design review phase completion will the request for change be allowed to processed as either a CN or request for deviation (RFD).