We know both Google and Bing prefer you go with a responsive design for search engine optimization purposes. But that doesn't mean that you should just jump in to it without thinking.
Switching a legacy site to a responsive design takes careful consideration. After you decide responsive is indeed the way to go, over dynamic serving or separate web sites, then you need to do all your SEO checkpoints as if you are launching a brand new design.
The basic principles when launching a brand new design apply to launching a responsive design (assuming you change all your HTML structure to make it happen). You want to make sure of the following, if possible:
- Your URLs stay the same and if not, you have proper redirects in place
- Page titles remain the same
- Content on the page the same
- Navigation to the content stays pretty much the same
- Images and graphics on the page remain the same
- All the meta data remains the same
- All the basic SEO principles for a redesign are went over
You want to launch the new responsive design without changing too much, outside of the HTML and design. You want your content, images, URLs, navigation and so forth to all be the same as it was.
If you do all of that, you really should not see a change in rankings or indexation by the search engines. But like with any major design revamp, you need to make sure you test, test and test to make sure you didn't forget anything. And after you launch, watch those 404s, errors and analytics for things you may have missed - because if catch them fast and fix them fast, all should be good with your rankings.
Forum discussion at WebmasterWorld.

Comments:
Daniel Carlyon
01/22/2013 01:53 pm
Some very good points. It's not an easy task both technically and SEO wise. I wonder if there are any stories of people's sites tanking because they have changed too much when they went responsive?
James Bavington
01/22/2013 02:10 pm
Also worth noting that you also get to collate your social shares, as there is only one URL per page.
Oleg Korneitchouk
01/22/2013 03:27 pm
For sure, we've had several clients come to us because their rankings dropped after a redesign. People seem to assume that if you are currently ranking, totally revamping your site won't affect rankings. As Barry pointed out, try to keep all the previous elements remaining on the page as that improves the likelihood of stable rankings. (Use archive.org to see the previous site versions)
Takeshi Young
01/22/2013 08:41 pm
I'm currently working on a mobile design for one of my existing sites using dynamic serving. Is it necessary to have schema.org semantic markup on the mobile design as well, or just on the actual website?
Jim Hobson
01/23/2013 12:54 am
Thank you for this valuable information! This month we've had three clients asking about responsive web design. This heads-up will definitely save us from some ugly surprises.
Dario Petkovic
01/23/2013 07:01 am
I've done many website upgrades from .html pages to wordpress and number one thing as rightly placed on Barry's list are 301 redirects. Google picks that up and re-assigns all the rankings to the new page.
Vikash Khetan
01/23/2013 08:42 am
Just a point add here, when you think of removing any of the urls in process of creating a new design, then please do not redirect your 404 pages to your homepage, it hurts and if you 404 hurts, then it doen't. Its quite natural to have 404 pages on any website (even google has it)
Austin Geraci
01/23/2013 08:43 pm
You really can apply this to any Website Re-design..
Shaina
01/25/2013 07:24 pm
Thanks for sharing this info. As I was reading your article, I couldn't help but feel that these recommendations seem shortsighted. If a company's site architecture, content, metadata, etc. is up to par, your advice may apply. However, if the architecture and content are a mess, just putting a new shiny layer on top of it isn't going to bode well for the user experience or SEO, especially since each algorithm update seems to be putting more and more emphasis on these elements. What are your thoughts on how this advice applies to the *future* of SEO and the overall user experience?
Alisha
03/08/2013 10:11 pm
Your suggestion is to make sure everything stays the same? really? I don't know about that one. I agree with Shaina's comment. If you're going to redesign the site; shouldn't the new site be more user friendly and accessible with fewer duplicate content issues and a stronger internal linking structure? As long as your SEO elements and redirects are in place, I'd think you'd come out ahead in the end.