Hi, I feel a number of factors are important when optimizing a web site, including the content and structure of it, page layout, the HTML meta-tags and the submission process. Here are some most important factors which we should be taken care of: Site Overview * Current search engine crawl/ visibility * Web Site index status * Search Engine review(Any ban/ penalty) Site Usability & Accessibility * Website goal * Initial design impact * Navigation analysis * W3C validation * Content Duplication Check Technical Analysis * Canonical Issues of the website * Domain Info/ Domain name strategy * Site architecture & Layout * Technical SEO suggestions * Server Type Information * Coding Check * Invisible Text Check Key Phrase Analysis * Key phrase research process * Main key words/ phrase identification * Site SEO Gap Analysis * Keyword suggestions & Targeting On-site Optimization * URL Rewriting * Title tags reviews & suggestions * Content quality review * Meta Tags review * Anchor link structure * Internal Link Structure Off-site Optimization * External Links * Directories * Linking strategy overview & many other factors. Please add some other which you feel important & missing here.