When multiple URLs are near-duplicates Google will choose one and discard the others. This is to ensure that users are not annoyed by multiple URLs which have the same or very very nearly the same and meet a search query in the same context and with the same intent equally well. Many ecommerce sites fall foul to cannibalisation (cannibalization) of their own SEO success because they have within their site a number of mistakes they make with regards to such issues as canonicalization, inconsistent internal link signals, semantic misalignment of intent in site categories and sections, incorrect implementation of href lang internationalization, and other 'clues' which search engines use to identify 'the best' version or source of information for a search query. Here we identify some of the symptoms of SEO cannibalization, and seek to find some solutions which can help to increase visibility for target pages in websites