Whenever webmasters try to implement big changes to a website, they are always conscious of minimizing the effect on the search rankings. In this video, Matt Cutts gives concrete examples of what people can do to soften any blow that might occur as a consequence of shifting from HTML to CMS.

1. Introduce a Gradual Change – If all aspects of a website are changed at once and the ranking dips afterwards, then it would be difficult to pinpoint the exact cause of the drop. A better way to go about it is to make incremental changes affecting one aspect at a time and observing its effects, if any, before proceeding.  2. Start with the Layout — If migrating to the CMS will alter the layout, then webmasters are advised to try to copy this new layout using HTML. This can be done to a few individual pages in order to find out any search engine and end-user reactions in a controlled manner.

3. Keep the URL Structure Constant — As much as possible, let the URL structure remain the same. Changes on this front could potentially have an adverse effect on page scores. Study the CMS to be used to figure out how to retain the addresses.

Video Link:

What are some best practices for moving to a new CMS? –