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If an entire structure is changing then it depends to what depth. Basically, are there rules you can apply? i.e. domain.com/products/[product-group]/product-name/ to domain.com/[category]/product-name/ If there are rules like that then it reduces you work to pattern matching URLs and redirecting them accordingly, and I can post you .htaccess entries. If the product names/URL and categories etc are changing then it may boil down to redirecting each URL individually, which for an e-commerce site will be a huge manual job. On the upside, you know for certain URL A --> URL B. Let me know what applies and I'll let you know what to do Have had to handle domain moves (we are just about to do it again for our own site) so I know it's a headache you want to get right first time. Oh and make sure you've got BOTH the old and new domains authorised in Google Webmaster Tools before you do the move